1 /*
2 * Copyright (c) 1999, 2020, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // no precompiled headers
26 #include "jvm.h"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "compiler/compileBroker.hpp"
33 #include "compiler/disassembler.hpp"
34 #include "interpreter/interpreter.hpp"
35 #include "logging/log.hpp"
36 #include "logging/logStream.hpp"
37 #include "memory/allocation.inline.hpp"
38 #include "memory/filemap.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "os_bsd.inline.hpp"
41 #include "os_posix.inline.hpp"
42 #include "os_share_bsd.hpp"
43 #include "prims/jniFastGetField.hpp"
44 #include "prims/jvm_misc.hpp"
45 #include "runtime/arguments.hpp"
46 #include "runtime/atomic.hpp"
47 #include "runtime/extendedPC.hpp"
48 #include "runtime/globals.hpp"
49 #include "runtime/interfaceSupport.inline.hpp"
50 #include "runtime/java.hpp"
51 #include "runtime/javaCalls.hpp"
52 #include "runtime/mutexLocker.hpp"
53 #include "runtime/objectMonitor.hpp"
54 #include "runtime/osThread.hpp"
55 #include "runtime/perfMemory.hpp"
56 #include "runtime/semaphore.hpp"
57 #include "runtime/sharedRuntime.hpp"
58 #include "runtime/statSampler.hpp"
59 #include "runtime/stubRoutines.hpp"
60 #include "runtime/thread.inline.hpp"
61 #include "runtime/threadCritical.hpp"
62 #include "runtime/timer.hpp"
63 #include "services/attachListener.hpp"
64 #include "services/memTracker.hpp"
65 #include "services/runtimeService.hpp"
66 #include "utilities/align.hpp"
67 #include "utilities/decoder.hpp"
68 #include "utilities/defaultStream.hpp"
69 #include "utilities/events.hpp"
70 #include "utilities/growableArray.hpp"
71 #include "utilities/vmError.hpp"
72
73 // put OS-includes here
74 # include <dlfcn.h>
75 # include <errno.h>
76 # include <fcntl.h>
77 # include <inttypes.h>
78 # include <poll.h>
79 # include <pthread.h>
80 # include <pwd.h>
81 # include <signal.h>
82 # include <stdint.h>
83 # include <stdio.h>
84 # include <string.h>
85 # include <sys/ioctl.h>
86 # include <sys/mman.h>
87 # include <sys/param.h>
88 # include <sys/resource.h>
89 # include <sys/socket.h>
90 # include <sys/stat.h>
91 # include <sys/syscall.h>
92 # include <sys/sysctl.h>
93 # include <sys/time.h>
94 # include <sys/times.h>
95 # include <sys/types.h>
96 # include <sys/wait.h>
97 # include <time.h>
98 # include <unistd.h>
99
100 #if defined(__FreeBSD__) || defined(__NetBSD__)
101 #include <elf.h>
102 #endif
103
104 #ifdef __APPLE__
105 #include <mach-o/dyld.h>
106 #endif
107
108 #ifndef MAP_ANONYMOUS
109 #define MAP_ANONYMOUS MAP_ANON
110 #endif
111
112 #define MAX_PATH (2 * K)
113
114 // for timer info max values which include all bits
115 #define ALL_64_BITS CONST64(0xFFFFFFFFFFFFFFFF)
116
117 ////////////////////////////////////////////////////////////////////////////////
118 // global variables
119 julong os::Bsd::_physical_memory = 0;
120
121 #ifdef __APPLE__
122 mach_timebase_info_data_t os::Bsd::_timebase_info = {0, 0};
123 volatile uint64_t os::Bsd::_max_abstime = 0;
124 #else
125 int (*os::Bsd::_clock_gettime)(clockid_t, struct timespec *) = NULL;
126 #endif
127 pthread_t os::Bsd::_main_thread;
128 int os::Bsd::_page_size = -1;
129
130 static jlong initial_time_count=0;
131
132 static int clock_tics_per_sec = 100;
133
134 // For diagnostics to print a message once. see run_periodic_checks
135 static sigset_t check_signal_done;
136 static bool check_signals = true;
137
138 // Signal number used to suspend/resume a thread
139
140 // do not use any signal number less than SIGSEGV, see 4355769
141 static int SR_signum = SIGUSR2;
142 sigset_t SR_sigset;
143
144
145 ////////////////////////////////////////////////////////////////////////////////
146 // utility functions
147
148 static int SR_initialize();
149
150 julong os::available_memory() {
151 return Bsd::available_memory();
152 }
153
154 // available here means free
155 julong os::Bsd::available_memory() {
156 uint64_t available = physical_memory() >> 2;
157 #ifdef __APPLE__
158 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
159 vm_statistics64_data_t vmstat;
160 kern_return_t kerr = host_statistics64(mach_host_self(), HOST_VM_INFO64,
161 (host_info64_t)&vmstat, &count);
162 assert(kerr == KERN_SUCCESS,
163 "host_statistics64 failed - check mach_host_self() and count");
164 if (kerr == KERN_SUCCESS) {
165 available = vmstat.free_count * os::vm_page_size();
166 }
167 #endif
168 return available;
169 }
170
171 // for more info see :
172 // https://man.openbsd.org/sysctl.2
173 void os::Bsd::print_uptime_info(outputStream* st) {
174 struct timeval boottime;
175 size_t len = sizeof(boottime);
176 int mib[2];
177 mib[0] = CTL_KERN;
178 mib[1] = KERN_BOOTTIME;
179
180 if (sysctl(mib, 2, &boottime, &len, NULL, 0) >= 0) {
181 time_t bootsec = boottime.tv_sec;
182 time_t currsec = time(NULL);
183 os::print_dhm(st, "OS uptime:", (long) difftime(currsec, bootsec));
184 }
185 }
186
187 julong os::physical_memory() {
188 return Bsd::physical_memory();
189 }
190
191 // Return true if user is running as root.
192
193 bool os::have_special_privileges() {
194 static bool init = false;
195 static bool privileges = false;
196 if (!init) {
197 privileges = (getuid() != geteuid()) || (getgid() != getegid());
198 init = true;
199 }
200 return privileges;
201 }
202
203
204
205 // Cpu architecture string
206 #if defined(ZERO)
207 static char cpu_arch[] = ZERO_LIBARCH;
208 #elif defined(IA64)
209 static char cpu_arch[] = "ia64";
210 #elif defined(IA32)
211 static char cpu_arch[] = "i386";
212 #elif defined(AMD64)
213 static char cpu_arch[] = "amd64";
214 #elif defined(ARM)
215 static char cpu_arch[] = "arm";
216 #elif defined(PPC32)
217 static char cpu_arch[] = "ppc";
218 #elif defined(SPARC)
219 #ifdef _LP64
220 static char cpu_arch[] = "sparcv9";
221 #else
222 static char cpu_arch[] = "sparc";
223 #endif
224 #else
225 #error Add appropriate cpu_arch setting
226 #endif
227
228 // Compiler variant
229 #ifdef COMPILER2
230 #define COMPILER_VARIANT "server"
231 #else
232 #define COMPILER_VARIANT "client"
233 #endif
234
235
236 void os::Bsd::initialize_system_info() {
237 int mib[2];
238 size_t len;
239 int cpu_val;
240 julong mem_val;
241
242 // get processors count via hw.ncpus sysctl
243 mib[0] = CTL_HW;
244 mib[1] = HW_NCPU;
245 len = sizeof(cpu_val);
246 if (sysctl(mib, 2, &cpu_val, &len, NULL, 0) != -1 && cpu_val >= 1) {
247 assert(len == sizeof(cpu_val), "unexpected data size");
248 set_processor_count(cpu_val);
249 } else {
250 set_processor_count(1); // fallback
251 }
252
253 // get physical memory via hw.memsize sysctl (hw.memsize is used
254 // since it returns a 64 bit value)
255 mib[0] = CTL_HW;
256
257 #if defined (HW_MEMSIZE) // Apple
258 mib[1] = HW_MEMSIZE;
259 #elif defined(HW_PHYSMEM) // Most of BSD
260 mib[1] = HW_PHYSMEM;
261 #elif defined(HW_REALMEM) // Old FreeBSD
262 mib[1] = HW_REALMEM;
263 #else
264 #error No ways to get physmem
265 #endif
266
267 len = sizeof(mem_val);
268 if (sysctl(mib, 2, &mem_val, &len, NULL, 0) != -1) {
269 assert(len == sizeof(mem_val), "unexpected data size");
270 _physical_memory = mem_val;
271 } else {
272 _physical_memory = 256 * 1024 * 1024; // fallback (XXXBSD?)
273 }
274
275 #ifdef __OpenBSD__
276 {
277 // limit _physical_memory memory view on OpenBSD since
278 // datasize rlimit restricts us anyway.
279 struct rlimit limits;
280 getrlimit(RLIMIT_DATA, &limits);
281 _physical_memory = MIN2(_physical_memory, (julong)limits.rlim_cur);
282 }
283 #endif
284 }
285
286 #ifdef __APPLE__
287 static const char *get_home() {
288 const char *home_dir = ::getenv("HOME");
289 if ((home_dir == NULL) || (*home_dir == '\0')) {
290 struct passwd *passwd_info = getpwuid(geteuid());
291 if (passwd_info != NULL) {
292 home_dir = passwd_info->pw_dir;
293 }
294 }
295
296 return home_dir;
297 }
298 #endif
299
300 void os::init_system_properties_values() {
301 // The next steps are taken in the product version:
302 //
303 // Obtain the JAVA_HOME value from the location of libjvm.so.
304 // This library should be located at:
305 // <JAVA_HOME>/jre/lib/<arch>/{client|server}/libjvm.so.
306 //
307 // If "/jre/lib/" appears at the right place in the path, then we
308 // assume libjvm.so is installed in a JDK and we use this path.
309 //
310 // Otherwise exit with message: "Could not create the Java virtual machine."
311 //
312 // The following extra steps are taken in the debugging version:
313 //
314 // If "/jre/lib/" does NOT appear at the right place in the path
315 // instead of exit check for $JAVA_HOME environment variable.
316 //
317 // If it is defined and we are able to locate $JAVA_HOME/jre/lib/<arch>,
318 // then we append a fake suffix "hotspot/libjvm.so" to this path so
319 // it looks like libjvm.so is installed there
320 // <JAVA_HOME>/jre/lib/<arch>/hotspot/libjvm.so.
321 //
322 // Otherwise exit.
323 //
324 // Important note: if the location of libjvm.so changes this
325 // code needs to be changed accordingly.
326
327 // See ld(1):
328 // The linker uses the following search paths to locate required
329 // shared libraries:
330 // 1: ...
331 // ...
332 // 7: The default directories, normally /lib and /usr/lib.
333 #ifndef DEFAULT_LIBPATH
334 #ifndef OVERRIDE_LIBPATH
335 #define DEFAULT_LIBPATH "/lib:/usr/lib"
336 #else
337 #define DEFAULT_LIBPATH OVERRIDE_LIBPATH
338 #endif
339 #endif
340
341 // Base path of extensions installed on the system.
342 #define SYS_EXT_DIR "/usr/java/packages"
343 #define EXTENSIONS_DIR "/lib/ext"
344
345 #ifndef __APPLE__
346
347 // Buffer that fits several sprintfs.
348 // Note that the space for the colon and the trailing null are provided
349 // by the nulls included by the sizeof operator.
350 const size_t bufsize =
351 MAX2((size_t)MAXPATHLEN, // For dll_dir & friends.
352 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + sizeof(SYS_EXT_DIR) + sizeof(EXTENSIONS_DIR)); // extensions dir
353 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
354
355 // sysclasspath, java_home, dll_dir
356 {
357 char *pslash;
358 os::jvm_path(buf, bufsize);
359
360 // Found the full path to libjvm.so.
361 // Now cut the path to <java_home>/jre if we can.
362 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
363 pslash = strrchr(buf, '/');
364 if (pslash != NULL) {
365 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
366 }
367 Arguments::set_dll_dir(buf);
368
369 if (pslash != NULL) {
370 pslash = strrchr(buf, '/');
371 if (pslash != NULL) {
372 *pslash = '\0'; // Get rid of /<arch>.
373 pslash = strrchr(buf, '/');
374 if (pslash != NULL) {
375 *pslash = '\0'; // Get rid of /lib.
376 }
377 }
378 }
379 Arguments::set_java_home(buf);
380 if (!set_boot_path('/', ':')) {
381 vm_exit_during_initialization("Failed setting boot class path.", NULL);
382 }
383 }
384
385 // Where to look for native libraries.
386 //
387 // Note: Due to a legacy implementation, most of the library path
388 // is set in the launcher. This was to accomodate linking restrictions
389 // on legacy Bsd implementations (which are no longer supported).
390 // Eventually, all the library path setting will be done here.
391 //
392 // However, to prevent the proliferation of improperly built native
393 // libraries, the new path component /usr/java/packages is added here.
394 // Eventually, all the library path setting will be done here.
395 {
396 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
397 // should always exist (until the legacy problem cited above is
398 // addressed).
399 const char *v = ::getenv("LD_LIBRARY_PATH");
400 const char *v_colon = ":";
401 if (v == NULL) { v = ""; v_colon = ""; }
402 // That's +1 for the colon and +1 for the trailing '\0'.
403 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
404 strlen(v) + 1 +
405 sizeof(SYS_EXT_DIR) + sizeof("/lib/") + strlen(cpu_arch) + sizeof(DEFAULT_LIBPATH) + 1,
406 mtInternal);
407 sprintf(ld_library_path, "%s%s" SYS_EXT_DIR "/lib/%s:" DEFAULT_LIBPATH, v, v_colon, cpu_arch);
408 Arguments::set_library_path(ld_library_path);
409 FREE_C_HEAP_ARRAY(char, ld_library_path);
410 }
411
412 // Extensions directories.
413 sprintf(buf, "%s" EXTENSIONS_DIR ":" SYS_EXT_DIR EXTENSIONS_DIR, Arguments::get_java_home());
414 Arguments::set_ext_dirs(buf);
415
416 FREE_C_HEAP_ARRAY(char, buf);
417
418 #else // __APPLE__
419
420 #define SYS_EXTENSIONS_DIR "/Library/Java/Extensions"
421 #define SYS_EXTENSIONS_DIRS SYS_EXTENSIONS_DIR ":/Network" SYS_EXTENSIONS_DIR ":/System" SYS_EXTENSIONS_DIR ":/usr/lib/java"
422
423 const char *user_home_dir = get_home();
424 // The null in SYS_EXTENSIONS_DIRS counts for the size of the colon after user_home_dir.
425 size_t system_ext_size = strlen(user_home_dir) + sizeof(SYS_EXTENSIONS_DIR) +
426 sizeof(SYS_EXTENSIONS_DIRS);
427
428 // Buffer that fits several sprintfs.
429 // Note that the space for the colon and the trailing null are provided
430 // by the nulls included by the sizeof operator.
431 const size_t bufsize =
432 MAX2((size_t)MAXPATHLEN, // for dll_dir & friends.
433 (size_t)MAXPATHLEN + sizeof(EXTENSIONS_DIR) + system_ext_size); // extensions dir
434 char *buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
435
436 // sysclasspath, java_home, dll_dir
437 {
438 char *pslash;
439 os::jvm_path(buf, bufsize);
440
441 // Found the full path to libjvm.so.
442 // Now cut the path to <java_home>/jre if we can.
443 *(strrchr(buf, '/')) = '\0'; // Get rid of /libjvm.so.
444 pslash = strrchr(buf, '/');
445 if (pslash != NULL) {
446 *pslash = '\0'; // Get rid of /{client|server|hotspot}.
447 }
448 #ifdef STATIC_BUILD
449 strcat(buf, "/lib");
450 #endif
451
452 Arguments::set_dll_dir(buf);
453
454 if (pslash != NULL) {
455 pslash = strrchr(buf, '/');
456 if (pslash != NULL) {
457 *pslash = '\0'; // Get rid of /lib.
458 }
459 }
460 Arguments::set_java_home(buf);
461 set_boot_path('/', ':');
462 }
463
464 // Where to look for native libraries.
465 //
466 // Note: Due to a legacy implementation, most of the library path
467 // is set in the launcher. This was to accomodate linking restrictions
468 // on legacy Bsd implementations (which are no longer supported).
469 // Eventually, all the library path setting will be done here.
470 //
471 // However, to prevent the proliferation of improperly built native
472 // libraries, the new path component /usr/java/packages is added here.
473 // Eventually, all the library path setting will be done here.
474 {
475 // Get the user setting of LD_LIBRARY_PATH, and prepended it. It
476 // should always exist (until the legacy problem cited above is
477 // addressed).
478 // Prepend the default path with the JAVA_LIBRARY_PATH so that the app launcher code
479 // can specify a directory inside an app wrapper
480 const char *l = ::getenv("JAVA_LIBRARY_PATH");
481 const char *l_colon = ":";
482 if (l == NULL) { l = ""; l_colon = ""; }
483
484 const char *v = ::getenv("DYLD_LIBRARY_PATH");
485 const char *v_colon = ":";
486 if (v == NULL) { v = ""; v_colon = ""; }
487
488 // Apple's Java6 has "." at the beginning of java.library.path.
489 // OpenJDK on Windows has "." at the end of java.library.path.
490 // OpenJDK on Linux and Solaris don't have "." in java.library.path
491 // at all. To ease the transition from Apple's Java6 to OpenJDK7,
492 // "." is appended to the end of java.library.path. Yes, this
493 // could cause a change in behavior, but Apple's Java6 behavior
494 // can be achieved by putting "." at the beginning of the
495 // JAVA_LIBRARY_PATH environment variable.
496 char *ld_library_path = NEW_C_HEAP_ARRAY(char,
497 strlen(v) + 1 + strlen(l) + 1 +
498 system_ext_size + 3,
499 mtInternal);
500 sprintf(ld_library_path, "%s%s%s%s%s" SYS_EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS ":.",
501 v, v_colon, l, l_colon, user_home_dir);
502 Arguments::set_library_path(ld_library_path);
503 FREE_C_HEAP_ARRAY(char, ld_library_path);
504 }
505
506 // Extensions directories.
507 //
508 // Note that the space for the colon and the trailing null are provided
509 // by the nulls included by the sizeof operator (so actually one byte more
510 // than necessary is allocated).
511 sprintf(buf, "%s" SYS_EXTENSIONS_DIR ":%s" EXTENSIONS_DIR ":" SYS_EXTENSIONS_DIRS,
512 user_home_dir, Arguments::get_java_home());
513 Arguments::set_ext_dirs(buf);
514
515 FREE_C_HEAP_ARRAY(char, buf);
516
517 #undef SYS_EXTENSIONS_DIR
518 #undef SYS_EXTENSIONS_DIRS
519
520 #endif // __APPLE__
521
522 #undef SYS_EXT_DIR
523 #undef EXTENSIONS_DIR
524 }
525
526 ////////////////////////////////////////////////////////////////////////////////
527 // breakpoint support
528
529 void os::breakpoint() {
530 BREAKPOINT;
531 }
532
533 extern "C" void breakpoint() {
534 // use debugger to set breakpoint here
535 }
536
537 ////////////////////////////////////////////////////////////////////////////////
538 // signal support
539
540 debug_only(static bool signal_sets_initialized = false);
541 static sigset_t unblocked_sigs, vm_sigs;
542
543 void os::Bsd::signal_sets_init() {
544 // Should also have an assertion stating we are still single-threaded.
545 assert(!signal_sets_initialized, "Already initialized");
546 // Fill in signals that are necessarily unblocked for all threads in
547 // the VM. Currently, we unblock the following signals:
548 // SHUTDOWN{1,2,3}_SIGNAL: for shutdown hooks support (unless over-ridden
549 // by -Xrs (=ReduceSignalUsage));
550 // BREAK_SIGNAL which is unblocked only by the VM thread and blocked by all
551 // other threads. The "ReduceSignalUsage" boolean tells us not to alter
552 // the dispositions or masks wrt these signals.
553 // Programs embedding the VM that want to use the above signals for their
554 // own purposes must, at this time, use the "-Xrs" option to prevent
555 // interference with shutdown hooks and BREAK_SIGNAL thread dumping.
556 // (See bug 4345157, and other related bugs).
557 // In reality, though, unblocking these signals is really a nop, since
558 // these signals are not blocked by default.
559 sigemptyset(&unblocked_sigs);
560 sigaddset(&unblocked_sigs, SIGILL);
561 sigaddset(&unblocked_sigs, SIGSEGV);
562 sigaddset(&unblocked_sigs, SIGBUS);
563 sigaddset(&unblocked_sigs, SIGFPE);
564 sigaddset(&unblocked_sigs, SR_signum);
565
566 if (!ReduceSignalUsage) {
567 if (!os::Posix::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
568 sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
569
570 }
571 if (!os::Posix::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
572 sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
573 }
574 if (!os::Posix::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
575 sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
576 }
577 }
578 // Fill in signals that are blocked by all but the VM thread.
579 sigemptyset(&vm_sigs);
580 if (!ReduceSignalUsage) {
581 sigaddset(&vm_sigs, BREAK_SIGNAL);
582 }
583 debug_only(signal_sets_initialized = true);
584
585 }
586
587 // These are signals that are unblocked while a thread is running Java.
588 // (For some reason, they get blocked by default.)
589 sigset_t* os::Bsd::unblocked_signals() {
590 assert(signal_sets_initialized, "Not initialized");
591 return &unblocked_sigs;
592 }
593
594 // These are the signals that are blocked while a (non-VM) thread is
595 // running Java. Only the VM thread handles these signals.
596 sigset_t* os::Bsd::vm_signals() {
597 assert(signal_sets_initialized, "Not initialized");
598 return &vm_sigs;
599 }
600
601 void os::Bsd::hotspot_sigmask(Thread* thread) {
602
603 //Save caller's signal mask before setting VM signal mask
604 sigset_t caller_sigmask;
605 pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
606
607 OSThread* osthread = thread->osthread();
608 osthread->set_caller_sigmask(caller_sigmask);
609
610 pthread_sigmask(SIG_UNBLOCK, os::Bsd::unblocked_signals(), NULL);
611
612 if (!ReduceSignalUsage) {
613 if (thread->is_VM_thread()) {
614 // Only the VM thread handles BREAK_SIGNAL ...
615 pthread_sigmask(SIG_UNBLOCK, vm_signals(), NULL);
616 } else {
617 // ... all other threads block BREAK_SIGNAL
618 pthread_sigmask(SIG_BLOCK, vm_signals(), NULL);
619 }
620 }
621 }
622
623
624 //////////////////////////////////////////////////////////////////////////////
625 // create new thread
626
627 #ifdef __APPLE__
628 // library handle for calling objc_registerThreadWithCollector()
629 // without static linking to the libobjc library
630 #define OBJC_LIB "/usr/lib/libobjc.dylib"
631 #define OBJC_GCREGISTER "objc_registerThreadWithCollector"
632 typedef void (*objc_registerThreadWithCollector_t)();
633 extern "C" objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction;
634 objc_registerThreadWithCollector_t objc_registerThreadWithCollectorFunction = NULL;
635 #endif
636
637 // Thread start routine for all newly created threads
638 static void *thread_native_entry(Thread *thread) {
639
640 thread->record_stack_base_and_size();
641
642 // Try to randomize the cache line index of hot stack frames.
643 // This helps when threads of the same stack traces evict each other's
644 // cache lines. The threads can be either from the same JVM instance, or
645 // from different JVM instances. The benefit is especially true for
646 // processors with hyperthreading technology.
647 static int counter = 0;
648 int pid = os::current_process_id();
649 alloca(((pid ^ counter++) & 7) * 128);
650
651 thread->initialize_thread_current();
652
653 OSThread* osthread = thread->osthread();
654 Monitor* sync = osthread->startThread_lock();
655
656 osthread->set_thread_id(os::Bsd::gettid());
657
658 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
659 os::current_thread_id(), (uintx) pthread_self());
660
661 #ifdef __APPLE__
662 // Store unique OS X thread id used by SA
663 osthread->set_unique_thread_id();
664 #endif
665
666 // initialize signal mask for this thread
667 os::Bsd::hotspot_sigmask(thread);
668
669 // initialize floating point control register
670 os::Bsd::init_thread_fpu_state();
671
672 #ifdef __APPLE__
673 // register thread with objc gc
674 if (objc_registerThreadWithCollectorFunction != NULL) {
675 objc_registerThreadWithCollectorFunction();
676 }
677 #endif
678
679 // handshaking with parent thread
680 {
681 MutexLocker ml(sync, Mutex::_no_safepoint_check_flag);
682
683 // notify parent thread
684 osthread->set_state(INITIALIZED);
685 sync->notify_all();
686
687 // wait until os::start_thread()
688 while (osthread->get_state() == INITIALIZED) {
689 sync->wait_without_safepoint_check();
690 }
691 }
692
693 // call one more level start routine
694 thread->call_run();
695
696 // Note: at this point the thread object may already have deleted itself.
697 // Prevent dereferencing it from here on out.
698 thread = NULL;
699
700 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
701 os::current_thread_id(), (uintx) pthread_self());
702
703 return 0;
704 }
705
706 bool os::create_thread(Thread* thread, ThreadType thr_type,
707 size_t req_stack_size) {
708 assert(thread->osthread() == NULL, "caller responsible");
709
710 // Allocate the OSThread object
711 OSThread* osthread = new OSThread(NULL, NULL);
712 if (osthread == NULL) {
713 return false;
714 }
715
716 // set the correct thread state
717 osthread->set_thread_type(thr_type);
718
719 // Initial state is ALLOCATED but not INITIALIZED
720 osthread->set_state(ALLOCATED);
721
722 thread->set_osthread(osthread);
723
724 // init thread attributes
725 pthread_attr_t attr;
726 pthread_attr_init(&attr);
727 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
728
729 // calculate stack size if it's not specified by caller
730 size_t stack_size = os::Posix::get_initial_stack_size(thr_type, req_stack_size);
731 int status = pthread_attr_setstacksize(&attr, stack_size);
732 assert_status(status == 0, status, "pthread_attr_setstacksize");
733
734 ThreadState state;
735
736 {
737 pthread_t tid;
738 int ret = pthread_create(&tid, &attr, (void* (*)(void*)) thread_native_entry, thread);
739
740 char buf[64];
741 if (ret == 0) {
742 log_info(os, thread)("Thread started (pthread id: " UINTX_FORMAT ", attributes: %s). ",
743 (uintx) tid, os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
744 } else {
745 log_warning(os, thread)("Failed to start thread - pthread_create failed (%s) for attributes: %s.",
746 os::errno_name(ret), os::Posix::describe_pthread_attr(buf, sizeof(buf), &attr));
747 // Log some OS information which might explain why creating the thread failed.
748 log_info(os, thread)("Number of threads approx. running in the VM: %d", Threads::number_of_threads());
749 LogStream st(Log(os, thread)::info());
750 os::Posix::print_rlimit_info(&st);
751 os::print_memory_info(&st);
752 }
753
754 pthread_attr_destroy(&attr);
755
756 if (ret != 0) {
757 // Need to clean up stuff we've allocated so far
758 thread->set_osthread(NULL);
759 delete osthread;
760 return false;
761 }
762
763 // Store pthread info into the OSThread
764 osthread->set_pthread_id(tid);
765
766 // Wait until child thread is either initialized or aborted
767 {
768 Monitor* sync_with_child = osthread->startThread_lock();
769 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
770 while ((state = osthread->get_state()) == ALLOCATED) {
771 sync_with_child->wait_without_safepoint_check();
772 }
773 }
774
775 }
776
777 // Aborted due to thread limit being reached
778 if (state == ZOMBIE) {
779 thread->set_osthread(NULL);
780 delete osthread;
781 return false;
782 }
783
784 // The thread is returned suspended (in state INITIALIZED),
785 // and is started higher up in the call chain
786 assert(state == INITIALIZED, "race condition");
787 return true;
788 }
789
790 /////////////////////////////////////////////////////////////////////////////
791 // attach existing thread
792
793 // bootstrap the main thread
794 bool os::create_main_thread(JavaThread* thread) {
795 assert(os::Bsd::_main_thread == pthread_self(), "should be called inside main thread");
796 return create_attached_thread(thread);
797 }
798
799 bool os::create_attached_thread(JavaThread* thread) {
800 #ifdef ASSERT
801 thread->verify_not_published();
802 #endif
803
804 // Allocate the OSThread object
805 OSThread* osthread = new OSThread(NULL, NULL);
806
807 if (osthread == NULL) {
808 return false;
809 }
810
811 osthread->set_thread_id(os::Bsd::gettid());
812
813 #ifdef __APPLE__
814 // Store unique OS X thread id used by SA
815 osthread->set_unique_thread_id();
816 #endif
817
818 // Store pthread info into the OSThread
819 osthread->set_pthread_id(::pthread_self());
820
821 // initialize floating point control register
822 os::Bsd::init_thread_fpu_state();
823
824 // Initial thread state is RUNNABLE
825 osthread->set_state(RUNNABLE);
826
827 thread->set_osthread(osthread);
828
829 // initialize signal mask for this thread
830 // and save the caller's signal mask
831 os::Bsd::hotspot_sigmask(thread);
832
833 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ", pthread id: " UINTX_FORMAT ").",
834 os::current_thread_id(), (uintx) pthread_self());
835
836 return true;
837 }
838
839 void os::pd_start_thread(Thread* thread) {
840 OSThread * osthread = thread->osthread();
841 assert(osthread->get_state() != INITIALIZED, "just checking");
842 Monitor* sync_with_child = osthread->startThread_lock();
843 MutexLocker ml(sync_with_child, Mutex::_no_safepoint_check_flag);
844 sync_with_child->notify();
845 }
846
847 // Free Bsd resources related to the OSThread
848 void os::free_thread(OSThread* osthread) {
849 assert(osthread != NULL, "osthread not set");
850
851 // We are told to free resources of the argument thread,
852 // but we can only really operate on the current thread.
853 assert(Thread::current()->osthread() == osthread,
854 "os::free_thread but not current thread");
855
856 // Restore caller's signal mask
857 sigset_t sigmask = osthread->caller_sigmask();
858 pthread_sigmask(SIG_SETMASK, &sigmask, NULL);
859
860 delete osthread;
861 }
862
863 ////////////////////////////////////////////////////////////////////////////////
864 // time support
865
866 // Time since start-up in seconds to a fine granularity.
867 // Used by VMSelfDestructTimer and the MemProfiler.
868 double os::elapsedTime() {
869
870 return ((double)os::elapsed_counter()) / os::elapsed_frequency();
871 }
872
873 jlong os::elapsed_counter() {
874 return javaTimeNanos() - initial_time_count;
875 }
876
877 jlong os::elapsed_frequency() {
878 return NANOSECS_PER_SEC; // nanosecond resolution
879 }
880
881 bool os::supports_vtime() { return true; }
882
883 double os::elapsedVTime() {
884 // better than nothing, but not much
885 return elapsedTime();
886 }
887
888 jlong os::javaTimeMillis() {
889 timeval time;
890 int status = gettimeofday(&time, NULL);
891 assert(status != -1, "bsd error");
892 return jlong(time.tv_sec) * 1000 + jlong(time.tv_usec / 1000);
893 }
894
895 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
896 timeval time;
897 int status = gettimeofday(&time, NULL);
898 assert(status != -1, "bsd error");
899 seconds = jlong(time.tv_sec);
900 nanos = jlong(time.tv_usec) * 1000;
901 }
902
903 #ifndef __APPLE__
904 #ifndef CLOCK_MONOTONIC
905 #define CLOCK_MONOTONIC (1)
906 #endif
907 #endif
908
909 #ifdef __APPLE__
910 void os::Bsd::clock_init() {
911 mach_timebase_info(&_timebase_info);
912 }
913 #else
914 void os::Bsd::clock_init() {
915 struct timespec res;
916 struct timespec tp;
917 if (::clock_getres(CLOCK_MONOTONIC, &res) == 0 &&
918 ::clock_gettime(CLOCK_MONOTONIC, &tp) == 0) {
919 // yes, monotonic clock is supported
920 _clock_gettime = ::clock_gettime;
921 }
922 }
923 #endif
924
925
926
927 #ifdef __APPLE__
928
929 jlong os::javaTimeNanos() {
930 const uint64_t tm = mach_absolute_time();
931 const uint64_t now = (tm * Bsd::_timebase_info.numer) / Bsd::_timebase_info.denom;
932 const uint64_t prev = Bsd::_max_abstime;
933 if (now <= prev) {
934 return prev; // same or retrograde time;
935 }
936 const uint64_t obsv = Atomic::cmpxchg(&Bsd::_max_abstime, prev, now);
937 assert(obsv >= prev, "invariant"); // Monotonicity
938 // If the CAS succeeded then we're done and return "now".
939 // If the CAS failed and the observed value "obsv" is >= now then
940 // we should return "obsv". If the CAS failed and now > obsv > prv then
941 // some other thread raced this thread and installed a new value, in which case
942 // we could either (a) retry the entire operation, (b) retry trying to install now
943 // or (c) just return obsv. We use (c). No loop is required although in some cases
944 // we might discard a higher "now" value in deference to a slightly lower but freshly
945 // installed obsv value. That's entirely benign -- it admits no new orderings compared
946 // to (a) or (b) -- and greatly reduces coherence traffic.
947 // We might also condition (c) on the magnitude of the delta between obsv and now.
948 // Avoiding excessive CAS operations to hot RW locations is critical.
949 // See https://blogs.oracle.com/dave/entry/cas_and_cache_trivia_invalidate
950 return (prev == obsv) ? now : obsv;
951 }
952
953 #else // __APPLE__
954
955 jlong os::javaTimeNanos() {
956 if (os::supports_monotonic_clock()) {
957 struct timespec tp;
958 int status = Bsd::_clock_gettime(CLOCK_MONOTONIC, &tp);
959 assert(status == 0, "gettime error");
960 jlong result = jlong(tp.tv_sec) * (1000 * 1000 * 1000) + jlong(tp.tv_nsec);
961 return result;
962 } else {
963 timeval time;
964 int status = gettimeofday(&time, NULL);
965 assert(status != -1, "bsd error");
966 jlong usecs = jlong(time.tv_sec) * (1000 * 1000) + jlong(time.tv_usec);
967 return 1000 * usecs;
968 }
969 }
970
971 #endif // __APPLE__
972
973 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
974 if (os::supports_monotonic_clock()) {
975 info_ptr->max_value = ALL_64_BITS;
976
977 // CLOCK_MONOTONIC - amount of time since some arbitrary point in the past
978 info_ptr->may_skip_backward = false; // not subject to resetting or drifting
979 info_ptr->may_skip_forward = false; // not subject to resetting or drifting
980 } else {
981 // gettimeofday - based on time in seconds since the Epoch thus does not wrap
982 info_ptr->max_value = ALL_64_BITS;
983
984 // gettimeofday is a real time clock so it skips
985 info_ptr->may_skip_backward = true;
986 info_ptr->may_skip_forward = true;
987 }
988
989 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
990 }
991
992 // Return the real, user, and system times in seconds from an
993 // arbitrary fixed point in the past.
994 bool os::getTimesSecs(double* process_real_time,
995 double* process_user_time,
996 double* process_system_time) {
997 struct tms ticks;
998 clock_t real_ticks = times(&ticks);
999
1000 if (real_ticks == (clock_t) (-1)) {
1001 return false;
1002 } else {
1003 double ticks_per_second = (double) clock_tics_per_sec;
1004 *process_user_time = ((double) ticks.tms_utime) / ticks_per_second;
1005 *process_system_time = ((double) ticks.tms_stime) / ticks_per_second;
1006 *process_real_time = ((double) real_ticks) / ticks_per_second;
1007
1008 return true;
1009 }
1010 }
1011
1012
1013 char * os::local_time_string(char *buf, size_t buflen) {
1014 struct tm t;
1015 time_t long_time;
1016 time(&long_time);
1017 localtime_r(&long_time, &t);
1018 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
1019 t.tm_year + 1900, t.tm_mon + 1, t.tm_mday,
1020 t.tm_hour, t.tm_min, t.tm_sec);
1021 return buf;
1022 }
1023
1024 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
1025 return localtime_r(clock, res);
1026 }
1027
1028 ////////////////////////////////////////////////////////////////////////////////
1029 // runtime exit support
1030
1031 // Note: os::shutdown() might be called very early during initialization, or
1032 // called from signal handler. Before adding something to os::shutdown(), make
1033 // sure it is async-safe and can handle partially initialized VM.
1034 void os::shutdown() {
1035
1036 // allow PerfMemory to attempt cleanup of any persistent resources
1037 perfMemory_exit();
1038
1039 // needs to remove object in file system
1040 AttachListener::abort();
1041
1042 // flush buffered output, finish log files
1043 ostream_abort();
1044
1045 // Check for abort hook
1046 abort_hook_t abort_hook = Arguments::abort_hook();
1047 if (abort_hook != NULL) {
1048 abort_hook();
1049 }
1050
1051 }
1052
1053 // Note: os::abort() might be called very early during initialization, or
1054 // called from signal handler. Before adding something to os::abort(), make
1055 // sure it is async-safe and can handle partially initialized VM.
1056 void os::abort(bool dump_core, void* siginfo, const void* context) {
1057 os::shutdown();
1058 if (dump_core) {
1059 #ifndef PRODUCT
1060 fdStream out(defaultStream::output_fd());
1061 out.print_raw("Current thread is ");
1062 char buf[16];
1063 jio_snprintf(buf, sizeof(buf), UINTX_FORMAT, os::current_thread_id());
1064 out.print_raw_cr(buf);
1065 out.print_raw_cr("Dumping core ...");
1066 #endif
1067 ::abort(); // dump core
1068 }
1069
1070 ::exit(1);
1071 }
1072
1073 // Die immediately, no exit hook, no abort hook, no cleanup.
1074 // Dump a core file, if possible, for debugging.
1075 void os::die() {
1076 if (TestUnresponsiveErrorHandler && !CreateCoredumpOnCrash) {
1077 // For TimeoutInErrorHandlingTest.java, we just kill the VM
1078 // and don't take the time to generate a core file.
1079 os::signal_raise(SIGKILL);
1080 } else {
1081 // _exit() on BsdThreads only kills current thread
1082 ::abort();
1083 }
1084 }
1085
1086 // Information of current thread in variety of formats
1087 pid_t os::Bsd::gettid() {
1088 int retval = -1;
1089
1090 #ifdef __APPLE__ // XNU kernel
1091 mach_port_t port = mach_thread_self();
1092 guarantee(MACH_PORT_VALID(port), "just checking");
1093 mach_port_deallocate(mach_task_self(), port);
1094 return (pid_t)port;
1095
1096 #else
1097 #ifdef __FreeBSD__
1098 retval = syscall(SYS_thr_self);
1099 #else
1100 #ifdef __OpenBSD__
1101 retval = syscall(SYS_getthrid);
1102 #else
1103 #ifdef __NetBSD__
1104 retval = (pid_t) syscall(SYS__lwp_self);
1105 #endif
1106 #endif
1107 #endif
1108 #endif
1109
1110 if (retval == -1) {
1111 return getpid();
1112 }
1113 }
1114
1115 intx os::current_thread_id() {
1116 #ifdef __APPLE__
1117 return (intx)os::Bsd::gettid();
1118 #else
1119 return (intx)::pthread_self();
1120 #endif
1121 }
1122
1123 int os::current_process_id() {
1124 return (int)(getpid());
1125 }
1126
1127 // DLL functions
1128
1129 const char* os::dll_file_extension() { return JNI_LIB_SUFFIX; }
1130
1131 // This must be hard coded because it's the system's temporary
1132 // directory not the java application's temp directory, ala java.io.tmpdir.
1133 #ifdef __APPLE__
1134 // macosx has a secure per-user temporary directory
1135 char temp_path_storage[PATH_MAX];
1136 const char* os::get_temp_directory() {
1137 static char *temp_path = NULL;
1138 if (temp_path == NULL) {
1139 int pathSize = confstr(_CS_DARWIN_USER_TEMP_DIR, temp_path_storage, PATH_MAX);
1140 if (pathSize == 0 || pathSize > PATH_MAX) {
1141 strlcpy(temp_path_storage, "/tmp/", sizeof(temp_path_storage));
1142 }
1143 temp_path = temp_path_storage;
1144 }
1145 return temp_path;
1146 }
1147 #else // __APPLE__
1148 const char* os::get_temp_directory() { return "/tmp"; }
1149 #endif // __APPLE__
1150
1151 // check if addr is inside libjvm.so
1152 bool os::address_is_in_vm(address addr) {
1153 static address libjvm_base_addr;
1154 Dl_info dlinfo;
1155
1156 if (libjvm_base_addr == NULL) {
1157 if (dladdr(CAST_FROM_FN_PTR(void *, os::address_is_in_vm), &dlinfo) != 0) {
1158 libjvm_base_addr = (address)dlinfo.dli_fbase;
1159 }
1160 assert(libjvm_base_addr !=NULL, "Cannot obtain base address for libjvm");
1161 }
1162
1163 if (dladdr((void *)addr, &dlinfo) != 0) {
1164 if (libjvm_base_addr == (address)dlinfo.dli_fbase) return true;
1165 }
1166
1167 return false;
1168 }
1169
1170
1171 #define MACH_MAXSYMLEN 256
1172
1173 bool os::dll_address_to_function_name(address addr, char *buf,
1174 int buflen, int *offset,
1175 bool demangle) {
1176 // buf is not optional, but offset is optional
1177 assert(buf != NULL, "sanity check");
1178
1179 Dl_info dlinfo;
1180 char localbuf[MACH_MAXSYMLEN];
1181
1182 if (dladdr((void*)addr, &dlinfo) != 0) {
1183 // see if we have a matching symbol
1184 if (dlinfo.dli_saddr != NULL && dlinfo.dli_sname != NULL) {
1185 if (!(demangle && Decoder::demangle(dlinfo.dli_sname, buf, buflen))) {
1186 jio_snprintf(buf, buflen, "%s", dlinfo.dli_sname);
1187 }
1188 if (offset != NULL) *offset = addr - (address)dlinfo.dli_saddr;
1189 return true;
1190 }
1191 // no matching symbol so try for just file info
1192 if (dlinfo.dli_fname != NULL && dlinfo.dli_fbase != NULL) {
1193 if (Decoder::decode((address)(addr - (address)dlinfo.dli_fbase),
1194 buf, buflen, offset, dlinfo.dli_fname, demangle)) {
1195 return true;
1196 }
1197 }
1198
1199 // Handle non-dynamic manually:
1200 if (dlinfo.dli_fbase != NULL &&
1201 Decoder::decode(addr, localbuf, MACH_MAXSYMLEN, offset,
1202 dlinfo.dli_fbase)) {
1203 if (!(demangle && Decoder::demangle(localbuf, buf, buflen))) {
1204 jio_snprintf(buf, buflen, "%s", localbuf);
1205 }
1206 return true;
1207 }
1208 }
1209 buf[0] = '\0';
1210 if (offset != NULL) *offset = -1;
1211 return false;
1212 }
1213
1214 // ported from solaris version
1215 bool os::dll_address_to_library_name(address addr, char* buf,
1216 int buflen, int* offset) {
1217 // buf is not optional, but offset is optional
1218 assert(buf != NULL, "sanity check");
1219
1220 Dl_info dlinfo;
1221
1222 if (dladdr((void*)addr, &dlinfo) != 0) {
1223 if (dlinfo.dli_fname != NULL) {
1224 jio_snprintf(buf, buflen, "%s", dlinfo.dli_fname);
1225 }
1226 if (dlinfo.dli_fbase != NULL && offset != NULL) {
1227 *offset = addr - (address)dlinfo.dli_fbase;
1228 }
1229 return true;
1230 }
1231
1232 buf[0] = '\0';
1233 if (offset) *offset = -1;
1234 return false;
1235 }
1236
1237 // Loads .dll/.so and
1238 // in case of error it checks if .dll/.so was built for the
1239 // same architecture as Hotspot is running on
1240
1241 #ifdef __APPLE__
1242 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1243 #ifdef STATIC_BUILD
1244 return os::get_default_process_handle();
1245 #else
1246 log_info(os)("attempting shared library load of %s", filename);
1247
1248 void * result= ::dlopen(filename, RTLD_LAZY);
1249 if (result != NULL) {
1250 Events::log(NULL, "Loaded shared library %s", filename);
1251 // Successful loading
1252 log_info(os)("shared library load of %s was successful", filename);
1253 return result;
1254 }
1255
1256 const char* error_report = ::dlerror();
1257 if (error_report == NULL) {
1258 error_report = "dlerror returned no error description";
1259 }
1260 if (ebuf != NULL && ebuflen > 0) {
1261 // Read system error message into ebuf
1262 ::strncpy(ebuf, error_report, ebuflen-1);
1263 ebuf[ebuflen-1]='\0';
1264 }
1265 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1266 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1267
1268 return NULL;
1269 #endif // STATIC_BUILD
1270 }
1271 #else
1272 void * os::dll_load(const char *filename, char *ebuf, int ebuflen) {
1273 #ifdef STATIC_BUILD
1274 return os::get_default_process_handle();
1275 #else
1276 log_info(os)("attempting shared library load of %s", filename);
1277 void * result= ::dlopen(filename, RTLD_LAZY);
1278 if (result != NULL) {
1279 Events::log(NULL, "Loaded shared library %s", filename);
1280 // Successful loading
1281 log_info(os)("shared library load of %s was successful", filename);
1282 return result;
1283 }
1284
1285 Elf32_Ehdr elf_head;
1286
1287 const char* const error_report = ::dlerror();
1288 if (error_report == NULL) {
1289 error_report = "dlerror returned no error description";
1290 }
1291 if (ebuf != NULL && ebuflen > 0) {
1292 // Read system error message into ebuf
1293 ::strncpy(ebuf, error_report, ebuflen-1);
1294 ebuf[ebuflen-1]='\0';
1295 }
1296 Events::log(NULL, "Loading shared library %s failed, %s", filename, error_report);
1297 log_info(os)("shared library load of %s failed, %s", filename, error_report);
1298
1299 int diag_msg_max_length=ebuflen-strlen(ebuf);
1300 char* diag_msg_buf=ebuf+strlen(ebuf);
1301
1302 if (diag_msg_max_length==0) {
1303 // No more space in ebuf for additional diagnostics message
1304 return NULL;
1305 }
1306
1307
1308 int file_descriptor= ::open(filename, O_RDONLY | O_NONBLOCK);
1309
1310 if (file_descriptor < 0) {
1311 // Can't open library, report dlerror() message
1312 return NULL;
1313 }
1314
1315 bool failed_to_read_elf_head=
1316 (sizeof(elf_head)!=
1317 (::read(file_descriptor, &elf_head,sizeof(elf_head))));
1318
1319 ::close(file_descriptor);
1320 if (failed_to_read_elf_head) {
1321 // file i/o error - report dlerror() msg
1322 return NULL;
1323 }
1324
1325 typedef struct {
1326 Elf32_Half code; // Actual value as defined in elf.h
1327 Elf32_Half compat_class; // Compatibility of archs at VM's sense
1328 char elf_class; // 32 or 64 bit
1329 char endianess; // MSB or LSB
1330 char* name; // String representation
1331 } arch_t;
1332
1333 #ifndef EM_486
1334 #define EM_486 6 /* Intel 80486 */
1335 #endif
1336
1337 #ifndef EM_MIPS_RS3_LE
1338 #define EM_MIPS_RS3_LE 10 /* MIPS */
1339 #endif
1340
1341 #ifndef EM_PPC64
1342 #define EM_PPC64 21 /* PowerPC64 */
1343 #endif
1344
1345 #ifndef EM_S390
1346 #define EM_S390 22 /* IBM System/390 */
1347 #endif
1348
1349 #ifndef EM_IA_64
1350 #define EM_IA_64 50 /* HP/Intel IA-64 */
1351 #endif
1352
1353 #ifndef EM_X86_64
1354 #define EM_X86_64 62 /* AMD x86-64 */
1355 #endif
1356
1357 static const arch_t arch_array[]={
1358 {EM_386, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1359 {EM_486, EM_386, ELFCLASS32, ELFDATA2LSB, (char*)"IA 32"},
1360 {EM_IA_64, EM_IA_64, ELFCLASS64, ELFDATA2LSB, (char*)"IA 64"},
1361 {EM_X86_64, EM_X86_64, ELFCLASS64, ELFDATA2LSB, (char*)"AMD 64"},
1362 {EM_SPARC, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1363 {EM_SPARC32PLUS, EM_SPARC, ELFCLASS32, ELFDATA2MSB, (char*)"Sparc 32"},
1364 {EM_SPARCV9, EM_SPARCV9, ELFCLASS64, ELFDATA2MSB, (char*)"Sparc v9 64"},
1365 {EM_PPC, EM_PPC, ELFCLASS32, ELFDATA2MSB, (char*)"Power PC 32"},
1366 {EM_PPC64, EM_PPC64, ELFCLASS64, ELFDATA2MSB, (char*)"Power PC 64"},
1367 {EM_ARM, EM_ARM, ELFCLASS32, ELFDATA2LSB, (char*)"ARM"},
1368 {EM_S390, EM_S390, ELFCLASSNONE, ELFDATA2MSB, (char*)"IBM System/390"},
1369 {EM_ALPHA, EM_ALPHA, ELFCLASS64, ELFDATA2LSB, (char*)"Alpha"},
1370 {EM_MIPS_RS3_LE, EM_MIPS_RS3_LE, ELFCLASS32, ELFDATA2LSB, (char*)"MIPSel"},
1371 {EM_MIPS, EM_MIPS, ELFCLASS32, ELFDATA2MSB, (char*)"MIPS"},
1372 {EM_PARISC, EM_PARISC, ELFCLASS32, ELFDATA2MSB, (char*)"PARISC"},
1373 {EM_68K, EM_68K, ELFCLASS32, ELFDATA2MSB, (char*)"M68k"}
1374 };
1375
1376 #if (defined IA32)
1377 static Elf32_Half running_arch_code=EM_386;
1378 #elif (defined AMD64)
1379 static Elf32_Half running_arch_code=EM_X86_64;
1380 #elif (defined IA64)
1381 static Elf32_Half running_arch_code=EM_IA_64;
1382 #elif (defined __sparc) && (defined _LP64)
1383 static Elf32_Half running_arch_code=EM_SPARCV9;
1384 #elif (defined __sparc) && (!defined _LP64)
1385 static Elf32_Half running_arch_code=EM_SPARC;
1386 #elif (defined __powerpc64__)
1387 static Elf32_Half running_arch_code=EM_PPC64;
1388 #elif (defined __powerpc__)
1389 static Elf32_Half running_arch_code=EM_PPC;
1390 #elif (defined ARM)
1391 static Elf32_Half running_arch_code=EM_ARM;
1392 #elif (defined S390)
1393 static Elf32_Half running_arch_code=EM_S390;
1394 #elif (defined ALPHA)
1395 static Elf32_Half running_arch_code=EM_ALPHA;
1396 #elif (defined MIPSEL)
1397 static Elf32_Half running_arch_code=EM_MIPS_RS3_LE;
1398 #elif (defined PARISC)
1399 static Elf32_Half running_arch_code=EM_PARISC;
1400 #elif (defined MIPS)
1401 static Elf32_Half running_arch_code=EM_MIPS;
1402 #elif (defined M68K)
1403 static Elf32_Half running_arch_code=EM_68K;
1404 #else
1405 #error Method os::dll_load requires that one of following is defined:\
1406 IA32, AMD64, IA64, __sparc, __powerpc__, ARM, S390, ALPHA, MIPS, MIPSEL, PARISC, M68K
1407 #endif
1408
1409 // Identify compatability class for VM's architecture and library's architecture
1410 // Obtain string descriptions for architectures
1411
1412 arch_t lib_arch={elf_head.e_machine,0,elf_head.e_ident[EI_CLASS], elf_head.e_ident[EI_DATA], NULL};
1413 int running_arch_index=-1;
1414
1415 for (unsigned int i=0; i < ARRAY_SIZE(arch_array); i++) {
1416 if (running_arch_code == arch_array[i].code) {
1417 running_arch_index = i;
1418 }
1419 if (lib_arch.code == arch_array[i].code) {
1420 lib_arch.compat_class = arch_array[i].compat_class;
1421 lib_arch.name = arch_array[i].name;
1422 }
1423 }
1424
1425 assert(running_arch_index != -1,
1426 "Didn't find running architecture code (running_arch_code) in arch_array");
1427 if (running_arch_index == -1) {
1428 // Even though running architecture detection failed
1429 // we may still continue with reporting dlerror() message
1430 return NULL;
1431 }
1432
1433 if (lib_arch.endianess != arch_array[running_arch_index].endianess) {
1434 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: endianness mismatch)");
1435 return NULL;
1436 }
1437
1438 #ifndef S390
1439 if (lib_arch.elf_class != arch_array[running_arch_index].elf_class) {
1440 ::snprintf(diag_msg_buf, diag_msg_max_length-1," (Possible cause: architecture word width mismatch)");
1441 return NULL;
1442 }
1443 #endif // !S390
1444
1445 if (lib_arch.compat_class != arch_array[running_arch_index].compat_class) {
1446 if (lib_arch.name!=NULL) {
1447 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1448 " (Possible cause: can't load %s-bit .so on a %s-bit platform)",
1449 lib_arch.name, arch_array[running_arch_index].name);
1450 } else {
1451 ::snprintf(diag_msg_buf, diag_msg_max_length-1,
1452 " (Possible cause: can't load this .so (machine code=0x%x) on a %s-bit platform)",
1453 lib_arch.code,
1454 arch_array[running_arch_index].name);
1455 }
1456 }
1457
1458 return NULL;
1459 #endif // STATIC_BUILD
1460 }
1461 #endif // !__APPLE__
1462
1463 void* os::get_default_process_handle() {
1464 #ifdef __APPLE__
1465 // MacOS X needs to use RTLD_FIRST instead of RTLD_LAZY
1466 // to avoid finding unexpected symbols on second (or later)
1467 // loads of a library.
1468 return (void*)::dlopen(NULL, RTLD_FIRST);
1469 #else
1470 return (void*)::dlopen(NULL, RTLD_LAZY);
1471 #endif
1472 }
1473
1474 // XXX: Do we need a lock around this as per Linux?
1475 void* os::dll_lookup(void* handle, const char* name) {
1476 return dlsym(handle, name);
1477 }
1478
1479 int _print_dll_info_cb(const char * name, address base_address, address top_address, void * param) {
1480 outputStream * out = (outputStream *) param;
1481 out->print_cr(INTPTR_FORMAT " \t%s", (intptr_t)base_address, name);
1482 return 0;
1483 }
1484
1485 void os::print_dll_info(outputStream *st) {
1486 st->print_cr("Dynamic libraries:");
1487 if (get_loaded_modules_info(_print_dll_info_cb, (void *)st)) {
1488 st->print_cr("Error: Cannot print dynamic libraries.");
1489 }
1490 }
1491
1492 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1493 #ifdef RTLD_DI_LINKMAP
1494 Dl_info dli;
1495 void *handle;
1496 Link_map *map;
1497 Link_map *p;
1498
1499 if (dladdr(CAST_FROM_FN_PTR(void *, os::print_dll_info), &dli) == 0 ||
1500 dli.dli_fname == NULL) {
1501 return 1;
1502 }
1503 handle = dlopen(dli.dli_fname, RTLD_LAZY);
1504 if (handle == NULL) {
1505 return 1;
1506 }
1507 dlinfo(handle, RTLD_DI_LINKMAP, &map);
1508 if (map == NULL) {
1509 dlclose(handle);
1510 return 1;
1511 }
1512
1513 while (map->l_prev != NULL)
1514 map = map->l_prev;
1515
1516 while (map != NULL) {
1517 // Value for top_address is returned as 0 since we don't have any information about module size
1518 if (callback(map->l_name, (address)map->l_addr, (address)0, param)) {
1519 dlclose(handle);
1520 return 1;
1521 }
1522 map = map->l_next;
1523 }
1524
1525 dlclose(handle);
1526 #elif defined(__APPLE__)
1527 for (uint32_t i = 1; i < _dyld_image_count(); i++) {
1528 // Value for top_address is returned as 0 since we don't have any information about module size
1529 if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
1530 return 1;
1531 }
1532 }
1533 return 0;
1534 #else
1535 return 1;
1536 #endif
1537 }
1538
1539 void os::get_summary_os_info(char* buf, size_t buflen) {
1540 // These buffers are small because we want this to be brief
1541 // and not use a lot of stack while generating the hs_err file.
1542 char os[100];
1543 size_t size = sizeof(os);
1544 int mib_kern[] = { CTL_KERN, KERN_OSTYPE };
1545 if (sysctl(mib_kern, 2, os, &size, NULL, 0) < 0) {
1546 #ifdef __APPLE__
1547 strncpy(os, "Darwin", sizeof(os));
1548 #elif __OpenBSD__
1549 strncpy(os, "OpenBSD", sizeof(os));
1550 #else
1551 strncpy(os, "BSD", sizeof(os));
1552 #endif
1553 }
1554
1555 char release[100];
1556 size = sizeof(release);
1557 int mib_release[] = { CTL_KERN, KERN_OSRELEASE };
1558 if (sysctl(mib_release, 2, release, &size, NULL, 0) < 0) {
1559 // if error, leave blank
1560 strncpy(release, "", sizeof(release));
1561 }
1562 snprintf(buf, buflen, "%s %s", os, release);
1563 }
1564
1565 void os::print_os_info_brief(outputStream* st) {
1566 os::Posix::print_uname_info(st);
1567 }
1568
1569 void os::print_os_info(outputStream* st) {
1570 st->print("OS:");
1571
1572 os::Posix::print_uname_info(st);
1573
1574 os::Bsd::print_uptime_info(st);
1575
1576 os::Posix::print_rlimit_info(st);
1577
1578 os::Posix::print_load_average(st);
1579
1580 VM_Version::print_platform_virtualization_info(st);
1581 }
1582
1583 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1584 // Nothing to do for now.
1585 }
1586
1587 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1588 unsigned int mhz;
1589 size_t size = sizeof(mhz);
1590 int mib[] = { CTL_HW, HW_CPU_FREQ };
1591 if (sysctl(mib, 2, &mhz, &size, NULL, 0) < 0) {
1592 mhz = 1; // looks like an error but can be divided by
1593 } else {
1594 mhz /= 1000000; // reported in millions
1595 }
1596
1597 char model[100];
1598 size = sizeof(model);
1599 int mib_model[] = { CTL_HW, HW_MODEL };
1600 if (sysctl(mib_model, 2, model, &size, NULL, 0) < 0) {
1601 strncpy(model, cpu_arch, sizeof(model));
1602 }
1603
1604 char machine[100];
1605 size = sizeof(machine);
1606 int mib_machine[] = { CTL_HW, HW_MACHINE };
1607 if (sysctl(mib_machine, 2, machine, &size, NULL, 0) < 0) {
1608 strncpy(machine, "", sizeof(machine));
1609 }
1610
1611 snprintf(buf, buflen, "%s %s %d MHz", model, machine, mhz);
1612 }
1613
1614 void os::print_memory_info(outputStream* st) {
1615 xsw_usage swap_usage;
1616 size_t size = sizeof(swap_usage);
1617
1618 st->print("Memory:");
1619 st->print(" %dk page", os::vm_page_size()>>10);
1620
1621 st->print(", physical " UINT64_FORMAT "k",
1622 os::physical_memory() >> 10);
1623 st->print("(" UINT64_FORMAT "k free)",
1624 os::available_memory() >> 10);
1625
1626 if((sysctlbyname("vm.swapusage", &swap_usage, &size, NULL, 0) == 0) || (errno == ENOMEM)) {
1627 if (size >= offset_of(xsw_usage, xsu_used)) {
1628 st->print(", swap " UINT64_FORMAT "k",
1629 ((julong) swap_usage.xsu_total) >> 10);
1630 st->print("(" UINT64_FORMAT "k free)",
1631 ((julong) swap_usage.xsu_avail) >> 10);
1632 }
1633 }
1634
1635 st->cr();
1636 }
1637
1638 static void print_signal_handler(outputStream* st, int sig,
1639 char* buf, size_t buflen);
1640
1641 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1642 st->print_cr("Signal Handlers:");
1643 print_signal_handler(st, SIGSEGV, buf, buflen);
1644 print_signal_handler(st, SIGBUS , buf, buflen);
1645 print_signal_handler(st, SIGFPE , buf, buflen);
1646 print_signal_handler(st, SIGPIPE, buf, buflen);
1647 print_signal_handler(st, SIGXFSZ, buf, buflen);
1648 print_signal_handler(st, SIGILL , buf, buflen);
1649 print_signal_handler(st, SR_signum, buf, buflen);
1650 print_signal_handler(st, SHUTDOWN1_SIGNAL, buf, buflen);
1651 print_signal_handler(st, SHUTDOWN2_SIGNAL , buf, buflen);
1652 print_signal_handler(st, SHUTDOWN3_SIGNAL , buf, buflen);
1653 print_signal_handler(st, BREAK_SIGNAL, buf, buflen);
1654 }
1655
1656 static char saved_jvm_path[MAXPATHLEN] = {0};
1657
1658 // Find the full path to the current module, libjvm
1659 void os::jvm_path(char *buf, jint buflen) {
1660 // Error checking.
1661 if (buflen < MAXPATHLEN) {
1662 assert(false, "must use a large-enough buffer");
1663 buf[0] = '\0';
1664 return;
1665 }
1666 // Lazy resolve the path to current module.
1667 if (saved_jvm_path[0] != 0) {
1668 strcpy(buf, saved_jvm_path);
1669 return;
1670 }
1671
1672 char dli_fname[MAXPATHLEN];
1673 bool ret = dll_address_to_library_name(
1674 CAST_FROM_FN_PTR(address, os::jvm_path),
1675 dli_fname, sizeof(dli_fname), NULL);
1676 assert(ret, "cannot locate libjvm");
1677 char *rp = NULL;
1678 if (ret && dli_fname[0] != '\0') {
1679 rp = os::Posix::realpath(dli_fname, buf, buflen);
1680 }
1681 if (rp == NULL) {
1682 return;
1683 }
1684
1685 if (Arguments::sun_java_launcher_is_altjvm()) {
1686 // Support for the java launcher's '-XXaltjvm=<path>' option. Typical
1687 // value for buf is "<JAVA_HOME>/jre/lib/<arch>/<vmtype>/libjvm.so"
1688 // or "<JAVA_HOME>/jre/lib/<vmtype>/libjvm.dylib". If "/jre/lib/"
1689 // appears at the right place in the string, then assume we are
1690 // installed in a JDK and we're done. Otherwise, check for a
1691 // JAVA_HOME environment variable and construct a path to the JVM
1692 // being overridden.
1693
1694 const char *p = buf + strlen(buf) - 1;
1695 for (int count = 0; p > buf && count < 5; ++count) {
1696 for (--p; p > buf && *p != '/'; --p)
1697 /* empty */ ;
1698 }
1699
1700 if (strncmp(p, "/jre/lib/", 9) != 0) {
1701 // Look for JAVA_HOME in the environment.
1702 char* java_home_var = ::getenv("JAVA_HOME");
1703 if (java_home_var != NULL && java_home_var[0] != 0) {
1704 char* jrelib_p;
1705 int len;
1706
1707 // Check the current module name "libjvm"
1708 p = strrchr(buf, '/');
1709 assert(strstr(p, "/libjvm") == p, "invalid library name");
1710
1711 rp = os::Posix::realpath(java_home_var, buf, buflen);
1712 if (rp == NULL) {
1713 return;
1714 }
1715
1716 // determine if this is a legacy image or modules image
1717 // modules image doesn't have "jre" subdirectory
1718 len = strlen(buf);
1719 assert(len < buflen, "Ran out of buffer space");
1720 jrelib_p = buf + len;
1721
1722 // Add the appropriate library subdir
1723 snprintf(jrelib_p, buflen-len, "/jre/lib");
1724 if (0 != access(buf, F_OK)) {
1725 snprintf(jrelib_p, buflen-len, "/lib");
1726 }
1727
1728 // Add the appropriate client or server subdir
1729 len = strlen(buf);
1730 jrelib_p = buf + len;
1731 snprintf(jrelib_p, buflen-len, "/%s", COMPILER_VARIANT);
1732 if (0 != access(buf, F_OK)) {
1733 snprintf(jrelib_p, buflen-len, "%s", "");
1734 }
1735
1736 // If the path exists within JAVA_HOME, add the JVM library name
1737 // to complete the path to JVM being overridden. Otherwise fallback
1738 // to the path to the current library.
1739 if (0 == access(buf, F_OK)) {
1740 // Use current module name "libjvm"
1741 len = strlen(buf);
1742 snprintf(buf + len, buflen-len, "/libjvm%s", JNI_LIB_SUFFIX);
1743 } else {
1744 // Fall back to path of current library
1745 rp = os::Posix::realpath(dli_fname, buf, buflen);
1746 if (rp == NULL) {
1747 return;
1748 }
1749 }
1750 }
1751 }
1752 }
1753
1754 strncpy(saved_jvm_path, buf, MAXPATHLEN);
1755 saved_jvm_path[MAXPATHLEN - 1] = '\0';
1756 }
1757
1758 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1759 // no prefix required, not even "_"
1760 }
1761
1762 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1763 // no suffix required
1764 }
1765
1766 ////////////////////////////////////////////////////////////////////////////////
1767 // sun.misc.Signal support
1768
1769 static void UserHandler(int sig, void *siginfo, void *context) {
1770 // Ctrl-C is pressed during error reporting, likely because the error
1771 // handler fails to abort. Let VM die immediately.
1772 if (sig == SIGINT && VMError::is_error_reported()) {
1773 os::die();
1774 }
1775
1776 os::signal_notify(sig);
1777 }
1778
1779 void* os::user_handler() {
1780 return CAST_FROM_FN_PTR(void*, UserHandler);
1781 }
1782
1783 extern "C" {
1784 typedef void (*sa_handler_t)(int);
1785 typedef void (*sa_sigaction_t)(int, siginfo_t *, void *);
1786 }
1787
1788 void* os::signal(int signal_number, void* handler) {
1789 struct sigaction sigAct, oldSigAct;
1790
1791 sigfillset(&(sigAct.sa_mask));
1792 sigAct.sa_flags = SA_RESTART|SA_SIGINFO;
1793 sigAct.sa_handler = CAST_TO_FN_PTR(sa_handler_t, handler);
1794
1795 if (sigaction(signal_number, &sigAct, &oldSigAct)) {
1796 // -1 means registration failed
1797 return (void *)-1;
1798 }
1799
1800 return CAST_FROM_FN_PTR(void*, oldSigAct.sa_handler);
1801 }
1802
1803 void os::signal_raise(int signal_number) {
1804 ::raise(signal_number);
1805 }
1806
1807 // The following code is moved from os.cpp for making this
1808 // code platform specific, which it is by its very nature.
1809
1810 // Will be modified when max signal is changed to be dynamic
1811 int os::sigexitnum_pd() {
1812 return NSIG;
1813 }
1814
1815 // a counter for each possible signal value
1816 static volatile jint pending_signals[NSIG+1] = { 0 };
1817 static Semaphore* sig_sem = NULL;
1818
1819 static void jdk_misc_signal_init() {
1820 // Initialize signal structures
1821 ::memset((void*)pending_signals, 0, sizeof(pending_signals));
1822
1823 // Initialize signal semaphore
1824 sig_sem = new Semaphore();
1825 }
1826
1827 void os::signal_notify(int sig) {
1828 if (sig_sem != NULL) {
1829 Atomic::inc(&pending_signals[sig]);
1830 sig_sem->signal();
1831 } else {
1832 // Signal thread is not created with ReduceSignalUsage and jdk_misc_signal_init
1833 // initialization isn't called.
1834 assert(ReduceSignalUsage, "signal semaphore should be created");
1835 }
1836 }
1837
1838 static int check_pending_signals() {
1839 for (;;) {
1840 for (int i = 0; i < NSIG + 1; i++) {
1841 jint n = pending_signals[i];
1842 if (n > 0 && n == Atomic::cmpxchg(&pending_signals[i], n, n - 1)) {
1843 return i;
1844 }
1845 }
1846 JavaThread *thread = JavaThread::current();
1847 ThreadBlockInVM tbivm(thread);
1848
1849 bool threadIsSuspended;
1850 do {
1851 thread->set_suspend_equivalent();
1852 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
1853 sig_sem->wait();
1854
1855 // were we externally suspended while we were waiting?
1856 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
1857 if (threadIsSuspended) {
1858 // The semaphore has been incremented, but while we were waiting
1859 // another thread suspended us. We don't want to continue running
1860 // while suspended because that would surprise the thread that
1861 // suspended us.
1862 sig_sem->signal();
1863
1864 thread->java_suspend_self();
1865 }
1866 } while (threadIsSuspended);
1867 }
1868 }
1869
1870 int os::signal_wait() {
1871 return check_pending_signals();
1872 }
1873
1874 ////////////////////////////////////////////////////////////////////////////////
1875 // Virtual Memory
1876
1877 int os::vm_page_size() {
1878 // Seems redundant as all get out
1879 assert(os::Bsd::page_size() != -1, "must call os::init");
1880 return os::Bsd::page_size();
1881 }
1882
1883 // Solaris allocates memory by pages.
1884 int os::vm_allocation_granularity() {
1885 assert(os::Bsd::page_size() != -1, "must call os::init");
1886 return os::Bsd::page_size();
1887 }
1888
1889 // Rationale behind this function:
1890 // current (Mon Apr 25 20:12:18 MSD 2005) oprofile drops samples without executable
1891 // mapping for address (see lookup_dcookie() in the kernel module), thus we cannot get
1892 // samples for JITted code. Here we create private executable mapping over the code cache
1893 // and then we can use standard (well, almost, as mapping can change) way to provide
1894 // info for the reporting script by storing timestamp and location of symbol
1895 void bsd_wrap_code(char* base, size_t size) {
1896 static volatile jint cnt = 0;
1897
1898 if (!UseOprofile) {
1899 return;
1900 }
1901
1902 char buf[PATH_MAX + 1];
1903 int num = Atomic::add(&cnt, 1);
1904
1905 snprintf(buf, PATH_MAX + 1, "%s/hs-vm-%d-%d",
1906 os::get_temp_directory(), os::current_process_id(), num);
1907 unlink(buf);
1908
1909 int fd = ::open(buf, O_CREAT | O_RDWR, S_IRWXU);
1910
1911 if (fd != -1) {
1912 off_t rv = ::lseek(fd, size-2, SEEK_SET);
1913 if (rv != (off_t)-1) {
1914 if (::write(fd, "", 1) == 1) {
1915 mmap(base, size,
1916 PROT_READ|PROT_WRITE|PROT_EXEC,
1917 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE, fd, 0);
1918 }
1919 }
1920 ::close(fd);
1921 unlink(buf);
1922 }
1923 }
1924
1925 static void warn_fail_commit_memory(char* addr, size_t size, bool exec,
1926 int err) {
1927 warning("INFO: os::commit_memory(" INTPTR_FORMAT ", " SIZE_FORMAT
1928 ", %d) failed; error='%s' (errno=%d)", (intptr_t)addr, size, exec,
1929 os::errno_name(err), err);
1930 }
1931
1932 // NOTE: Bsd kernel does not really reserve the pages for us.
1933 // All it does is to check if there are enough free pages
1934 // left at the time of mmap(). This could be a potential
1935 // problem.
1936 bool os::pd_commit_memory(char* addr, size_t size, bool exec) {
1937 int prot = exec ? PROT_READ|PROT_WRITE|PROT_EXEC : PROT_READ|PROT_WRITE;
1938 #ifdef __OpenBSD__
1939 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
1940 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(addr), p2i(addr+size), prot);
1941 if (::mprotect(addr, size, prot) == 0) {
1942 return true;
1943 }
1944 #else
1945 uintptr_t res = (uintptr_t) ::mmap(addr, size, prot,
1946 MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0);
1947 if (res != (uintptr_t) MAP_FAILED) {
1948 return true;
1949 }
1950 #endif
1951
1952 // Warn about any commit errors we see in non-product builds just
1953 // in case mmap() doesn't work as described on the man page.
1954 NOT_PRODUCT(warn_fail_commit_memory(addr, size, exec, errno);)
1955
1956 return false;
1957 }
1958
1959 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
1960 bool exec) {
1961 // alignment_hint is ignored on this OS
1962 return pd_commit_memory(addr, size, exec);
1963 }
1964
1965 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
1966 const char* mesg) {
1967 assert(mesg != NULL, "mesg must be specified");
1968 if (!pd_commit_memory(addr, size, exec)) {
1969 // add extra info in product mode for vm_exit_out_of_memory():
1970 PRODUCT_ONLY(warn_fail_commit_memory(addr, size, exec, errno);)
1971 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
1972 }
1973 }
1974
1975 void os::pd_commit_memory_or_exit(char* addr, size_t size,
1976 size_t alignment_hint, bool exec,
1977 const char* mesg) {
1978 // alignment_hint is ignored on this OS
1979 pd_commit_memory_or_exit(addr, size, exec, mesg);
1980 }
1981
1982 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) {
1983 }
1984
1985 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) {
1986 ::madvise(addr, bytes, MADV_DONTNEED);
1987 }
1988
1989 void os::numa_make_global(char *addr, size_t bytes) {
1990 }
1991
1992 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) {
1993 }
1994
1995 bool os::numa_topology_changed() { return false; }
1996
1997 size_t os::numa_get_groups_num() {
1998 return 1;
1999 }
2000
2001 int os::numa_get_group_id() {
2002 return 0;
2003 }
2004
2005 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
2006 if (size > 0) {
2007 ids[0] = 0;
2008 return 1;
2009 }
2010 return 0;
2011 }
2012
2013 int os::numa_get_group_id_for_address(const void* address) {
2014 return 0;
2015 }
2016
2017 bool os::get_page_info(char *start, page_info* info) {
2018 return false;
2019 }
2020
2021 char *os::scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found) {
2022 return end;
2023 }
2024
2025
2026 bool os::pd_uncommit_memory(char* addr, size_t size) {
2027 #ifdef __OpenBSD__
2028 // XXX: Work-around mmap/MAP_FIXED bug temporarily on OpenBSD
2029 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with PROT_NONE", p2i(addr), p2i(addr+size));
2030 return ::mprotect(addr, size, PROT_NONE) == 0;
2031 #else
2032 uintptr_t res = (uintptr_t) ::mmap(addr, size, PROT_NONE,
2033 MAP_PRIVATE|MAP_FIXED|MAP_NORESERVE|MAP_ANONYMOUS, -1, 0);
2034 return res != (uintptr_t) MAP_FAILED;
2035 #endif
2036 }
2037
2038 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
2039 return os::commit_memory(addr, size, !ExecMem);
2040 }
2041
2042 // If this is a growable mapping, remove the guard pages entirely by
2043 // munmap()ping them. If not, just call uncommit_memory().
2044 bool os::remove_stack_guard_pages(char* addr, size_t size) {
2045 return os::uncommit_memory(addr, size);
2046 }
2047
2048 // If 'fixed' is true, anon_mmap() will attempt to reserve anonymous memory
2049 // at 'requested_addr'. If there are existing memory mappings at the same
2050 // location, however, they will be overwritten. If 'fixed' is false,
2051 // 'requested_addr' is only treated as a hint, the return value may or
2052 // may not start from the requested address. Unlike Bsd mmap(), this
2053 // function returns NULL to indicate failure.
2054 static char* anon_mmap(char* requested_addr, size_t bytes, bool fixed) {
2055 char * addr;
2056 int flags;
2057
2058 flags = MAP_PRIVATE | MAP_NORESERVE | MAP_ANONYMOUS;
2059 if (fixed) {
2060 assert((uintptr_t)requested_addr % os::Bsd::page_size() == 0, "unaligned address");
2061 flags |= MAP_FIXED;
2062 }
2063
2064 // Map reserved/uncommitted pages PROT_NONE so we fail early if we
2065 // touch an uncommitted page. Otherwise, the read/write might
2066 // succeed if we have enough swap space to back the physical page.
2067 addr = (char*)::mmap(requested_addr, bytes, PROT_NONE,
2068 flags, -1, 0);
2069
2070 return addr == MAP_FAILED ? NULL : addr;
2071 }
2072
2073 static int anon_munmap(char * addr, size_t size) {
2074 return ::munmap(addr, size) == 0;
2075 }
2076
2077 char* os::pd_reserve_memory(size_t bytes, char* requested_addr,
2078 size_t alignment_hint) {
2079 return anon_mmap(requested_addr, bytes, (requested_addr != NULL));
2080 }
2081
2082 bool os::pd_release_memory(char* addr, size_t size) {
2083 return anon_munmap(addr, size);
2084 }
2085
2086 static bool bsd_mprotect(char* addr, size_t size, int prot) {
2087 // Bsd wants the mprotect address argument to be page aligned.
2088 char* bottom = (char*)align_down((intptr_t)addr, os::Bsd::page_size());
2089
2090 // According to SUSv3, mprotect() should only be used with mappings
2091 // established by mmap(), and mmap() always maps whole pages. Unaligned
2092 // 'addr' likely indicates problem in the VM (e.g. trying to change
2093 // protection of malloc'ed or statically allocated memory). Check the
2094 // caller if you hit this assert.
2095 assert(addr == bottom, "sanity check");
2096
2097 size = align_up(pointer_delta(addr, bottom, 1) + size, os::Bsd::page_size());
2098 Events::log(NULL, "Protecting memory [" INTPTR_FORMAT "," INTPTR_FORMAT "] with protection modes %x", p2i(bottom), p2i(bottom+size), prot);
2099 return ::mprotect(bottom, size, prot) == 0;
2100 }
2101
2102 // Set protections specified
2103 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
2104 bool is_committed) {
2105 unsigned int p = 0;
2106 switch (prot) {
2107 case MEM_PROT_NONE: p = PROT_NONE; break;
2108 case MEM_PROT_READ: p = PROT_READ; break;
2109 case MEM_PROT_RW: p = PROT_READ|PROT_WRITE; break;
2110 case MEM_PROT_RWX: p = PROT_READ|PROT_WRITE|PROT_EXEC; break;
2111 default:
2112 ShouldNotReachHere();
2113 }
2114 // is_committed is unused.
2115 return bsd_mprotect(addr, bytes, p);
2116 }
2117
2118 bool os::guard_memory(char* addr, size_t size) {
2119 return bsd_mprotect(addr, size, PROT_NONE);
2120 }
2121
2122 bool os::unguard_memory(char* addr, size_t size) {
2123 return bsd_mprotect(addr, size, PROT_READ|PROT_WRITE);
2124 }
2125
2126 bool os::Bsd::hugetlbfs_sanity_check(bool warn, size_t page_size) {
2127 return false;
2128 }
2129
2130 // Large page support
2131
2132 static size_t _large_page_size = 0;
2133
2134 void os::large_page_init() {
2135 }
2136
2137
2138 char* os::pd_reserve_memory_special(size_t bytes, size_t alignment, char* req_addr, bool exec) {
2139 fatal("os::reserve_memory_special should not be called on BSD.");
2140 return NULL;
2141 }
2142
2143 bool os::pd_release_memory_special(char* base, size_t bytes) {
2144 fatal("os::release_memory_special should not be called on BSD.");
2145 return false;
2146 }
2147
2148 size_t os::large_page_size() {
2149 return _large_page_size;
2150 }
2151
2152 bool os::can_commit_large_page_memory() {
2153 // Does not matter, we do not support huge pages.
2154 return false;
2155 }
2156
2157 bool os::can_execute_large_page_memory() {
2158 // Does not matter, we do not support huge pages.
2159 return false;
2160 }
2161
2162 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr, int file_desc) {
2163 assert(file_desc >= 0, "file_desc is not valid");
2164 char* result = pd_attempt_reserve_memory_at(bytes, requested_addr);
2165 if (result != NULL) {
2166 if (replace_existing_mapping_with_file_mapping(result, bytes, file_desc) == NULL) {
2167 vm_exit_during_initialization(err_msg("Error in mapping Java heap at the given filesystem directory"));
2168 }
2169 }
2170 return result;
2171 }
2172
2173 // Reserve memory at an arbitrary address, only if that area is
2174 // available (and not reserved for something else).
2175
2176 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2177 // Assert only that the size is a multiple of the page size, since
2178 // that's all that mmap requires, and since that's all we really know
2179 // about at this low abstraction level. If we need higher alignment,
2180 // we can either pass an alignment to this method or verify alignment
2181 // in one of the methods further up the call chain. See bug 5044738.
2182 assert(bytes % os::vm_page_size() == 0, "reserving unexpected size block");
2183
2184 // Repeatedly allocate blocks until the block is allocated at the
2185 // right spot.
2186
2187 // Bsd mmap allows caller to pass an address as hint; give it a try first,
2188 // if kernel honors the hint then we can return immediately.
2189 char * addr = anon_mmap(requested_addr, bytes, false);
2190 if (addr == requested_addr) {
2191 return requested_addr;
2192 }
2193
2194 if (addr != NULL) {
2195 // mmap() is successful but it fails to reserve at the requested address
2196 anon_munmap(addr, bytes);
2197 }
2198
2199 return NULL;
2200 }
2201
2202 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
2203 void os::infinite_sleep() {
2204 while (true) { // sleep forever ...
2205 ::sleep(100); // ... 100 seconds at a time
2206 }
2207 }
2208
2209 // Used to convert frequent JVM_Yield() to nops
2210 bool os::dont_yield() {
2211 return DontYieldALot;
2212 }
2213
2214 void os::naked_yield() {
2215 sched_yield();
2216 }
2217
2218 ////////////////////////////////////////////////////////////////////////////////
2219 // thread priority support
2220
2221 // Note: Normal Bsd applications are run with SCHED_OTHER policy. SCHED_OTHER
2222 // only supports dynamic priority, static priority must be zero. For real-time
2223 // applications, Bsd supports SCHED_RR which allows static priority (1-99).
2224 // However, for large multi-threaded applications, SCHED_RR is not only slower
2225 // than SCHED_OTHER, but also very unstable (my volano tests hang hard 4 out
2226 // of 5 runs - Sep 2005).
2227 //
2228 // The following code actually changes the niceness of kernel-thread/LWP. It
2229 // has an assumption that setpriority() only modifies one kernel-thread/LWP,
2230 // not the entire user process, and user level threads are 1:1 mapped to kernel
2231 // threads. It has always been the case, but could change in the future. For
2232 // this reason, the code should not be used as default (ThreadPriorityPolicy=0).
2233 // It is only used when ThreadPriorityPolicy=1 and may require system level permission
2234 // (e.g., root privilege or CAP_SYS_NICE capability).
2235
2236 #if !defined(__APPLE__)
2237 int os::java_to_os_priority[CriticalPriority + 1] = {
2238 19, // 0 Entry should never be used
2239
2240 0, // 1 MinPriority
2241 3, // 2
2242 6, // 3
2243
2244 10, // 4
2245 15, // 5 NormPriority
2246 18, // 6
2247
2248 21, // 7
2249 25, // 8
2250 28, // 9 NearMaxPriority
2251
2252 31, // 10 MaxPriority
2253
2254 31 // 11 CriticalPriority
2255 };
2256 #else
2257 // Using Mach high-level priority assignments
2258 int os::java_to_os_priority[CriticalPriority + 1] = {
2259 0, // 0 Entry should never be used (MINPRI_USER)
2260
2261 27, // 1 MinPriority
2262 28, // 2
2263 29, // 3
2264
2265 30, // 4
2266 31, // 5 NormPriority (BASEPRI_DEFAULT)
2267 32, // 6
2268
2269 33, // 7
2270 34, // 8
2271 35, // 9 NearMaxPriority
2272
2273 36, // 10 MaxPriority
2274
2275 36 // 11 CriticalPriority
2276 };
2277 #endif
2278
2279 static int prio_init() {
2280 if (ThreadPriorityPolicy == 1) {
2281 if (geteuid() != 0) {
2282 if (!FLAG_IS_DEFAULT(ThreadPriorityPolicy) && !FLAG_IS_JIMAGE_RESOURCE(ThreadPriorityPolicy)) {
2283 warning("-XX:ThreadPriorityPolicy=1 may require system level permission, " \
2284 "e.g., being the root user. If the necessary permission is not " \
2285 "possessed, changes to priority will be silently ignored.");
2286 }
2287 }
2288 }
2289 if (UseCriticalJavaThreadPriority) {
2290 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
2291 }
2292 return 0;
2293 }
2294
2295 OSReturn os::set_native_priority(Thread* thread, int newpri) {
2296 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) return OS_OK;
2297
2298 #ifdef __OpenBSD__
2299 // OpenBSD pthread_setprio starves low priority threads
2300 return OS_OK;
2301 #elif defined(__FreeBSD__)
2302 int ret = pthread_setprio(thread->osthread()->pthread_id(), newpri);
2303 return (ret == 0) ? OS_OK : OS_ERR;
2304 #elif defined(__APPLE__) || defined(__NetBSD__)
2305 struct sched_param sp;
2306 int policy;
2307
2308 if (pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp) != 0) {
2309 return OS_ERR;
2310 }
2311
2312 sp.sched_priority = newpri;
2313 if (pthread_setschedparam(thread->osthread()->pthread_id(), policy, &sp) != 0) {
2314 return OS_ERR;
2315 }
2316
2317 return OS_OK;
2318 #else
2319 int ret = setpriority(PRIO_PROCESS, thread->osthread()->thread_id(), newpri);
2320 return (ret == 0) ? OS_OK : OS_ERR;
2321 #endif
2322 }
2323
2324 OSReturn os::get_native_priority(const Thread* const thread, int *priority_ptr) {
2325 if (!UseThreadPriorities || ThreadPriorityPolicy == 0) {
2326 *priority_ptr = java_to_os_priority[NormPriority];
2327 return OS_OK;
2328 }
2329
2330 errno = 0;
2331 #if defined(__OpenBSD__) || defined(__FreeBSD__)
2332 *priority_ptr = pthread_getprio(thread->osthread()->pthread_id());
2333 #elif defined(__APPLE__) || defined(__NetBSD__)
2334 int policy;
2335 struct sched_param sp;
2336
2337 int res = pthread_getschedparam(thread->osthread()->pthread_id(), &policy, &sp);
2338 if (res != 0) {
2339 *priority_ptr = -1;
2340 return OS_ERR;
2341 } else {
2342 *priority_ptr = sp.sched_priority;
2343 return OS_OK;
2344 }
2345 #else
2346 *priority_ptr = getpriority(PRIO_PROCESS, thread->osthread()->thread_id());
2347 #endif
2348 return (*priority_ptr != -1 || errno == 0 ? OS_OK : OS_ERR);
2349 }
2350
2351 ////////////////////////////////////////////////////////////////////////////////
2352 // suspend/resume support
2353
2354 // The low-level signal-based suspend/resume support is a remnant from the
2355 // old VM-suspension that used to be for java-suspension, safepoints etc,
2356 // within hotspot. Currently used by JFR's OSThreadSampler
2357 //
2358 // The remaining code is greatly simplified from the more general suspension
2359 // code that used to be used.
2360 //
2361 // The protocol is quite simple:
2362 // - suspend:
2363 // - sends a signal to the target thread
2364 // - polls the suspend state of the osthread using a yield loop
2365 // - target thread signal handler (SR_handler) sets suspend state
2366 // and blocks in sigsuspend until continued
2367 // - resume:
2368 // - sets target osthread state to continue
2369 // - sends signal to end the sigsuspend loop in the SR_handler
2370 //
2371 // Note that the SR_lock plays no role in this suspend/resume protocol,
2372 // but is checked for NULL in SR_handler as a thread termination indicator.
2373 // The SR_lock is, however, used by JavaThread::java_suspend()/java_resume() APIs.
2374 //
2375 // Note that resume_clear_context() and suspend_save_context() are needed
2376 // by SR_handler(), so that fetch_frame_from_ucontext() works,
2377 // which in part is used by:
2378 // - Forte Analyzer: AsyncGetCallTrace()
2379 // - StackBanging: get_frame_at_stack_banging_point()
2380
2381 static void resume_clear_context(OSThread *osthread) {
2382 osthread->set_ucontext(NULL);
2383 osthread->set_siginfo(NULL);
2384 }
2385
2386 static void suspend_save_context(OSThread *osthread, siginfo_t* siginfo, ucontext_t* context) {
2387 osthread->set_ucontext(context);
2388 osthread->set_siginfo(siginfo);
2389 }
2390
2391 // Handler function invoked when a thread's execution is suspended or
2392 // resumed. We have to be careful that only async-safe functions are
2393 // called here (Note: most pthread functions are not async safe and
2394 // should be avoided.)
2395 //
2396 // Note: sigwait() is a more natural fit than sigsuspend() from an
2397 // interface point of view, but sigwait() prevents the signal hander
2398 // from being run. libpthread would get very confused by not having
2399 // its signal handlers run and prevents sigwait()'s use with the
2400 // mutex granting granting signal.
2401 //
2402 // Currently only ever called on the VMThread or JavaThread
2403 //
2404 #ifdef __APPLE__
2405 static OSXSemaphore sr_semaphore;
2406 #else
2407 static PosixSemaphore sr_semaphore;
2408 #endif
2409
2410 static void SR_handler(int sig, siginfo_t* siginfo, ucontext_t* context) {
2411 // Save and restore errno to avoid confusing native code with EINTR
2412 // after sigsuspend.
2413 int old_errno = errno;
2414
2415 Thread* thread = Thread::current_or_null_safe();
2416 assert(thread != NULL, "Missing current thread in SR_handler");
2417
2418 // On some systems we have seen signal delivery get "stuck" until the signal
2419 // mask is changed as part of thread termination. Check that the current thread
2420 // has not already terminated (via SR_lock()) - else the following assertion
2421 // will fail because the thread is no longer a JavaThread as the ~JavaThread
2422 // destructor has completed.
2423
2424 if (thread->SR_lock() == NULL) {
2425 return;
2426 }
2427
2428 assert(thread->is_VM_thread() || thread->is_Java_thread(), "Must be VMThread or JavaThread");
2429
2430 OSThread* osthread = thread->osthread();
2431
2432 os::SuspendResume::State current = osthread->sr.state();
2433 if (current == os::SuspendResume::SR_SUSPEND_REQUEST) {
2434 suspend_save_context(osthread, siginfo, context);
2435
2436 // attempt to switch the state, we assume we had a SUSPEND_REQUEST
2437 os::SuspendResume::State state = osthread->sr.suspended();
2438 if (state == os::SuspendResume::SR_SUSPENDED) {
2439 sigset_t suspend_set; // signals for sigsuspend()
2440
2441 // get current set of blocked signals and unblock resume signal
2442 pthread_sigmask(SIG_BLOCK, NULL, &suspend_set);
2443 sigdelset(&suspend_set, SR_signum);
2444
2445 sr_semaphore.signal();
2446 // wait here until we are resumed
2447 while (1) {
2448 sigsuspend(&suspend_set);
2449
2450 os::SuspendResume::State result = osthread->sr.running();
2451 if (result == os::SuspendResume::SR_RUNNING) {
2452 sr_semaphore.signal();
2453 break;
2454 } else if (result != os::SuspendResume::SR_SUSPENDED) {
2455 ShouldNotReachHere();
2456 }
2457 }
2458
2459 } else if (state == os::SuspendResume::SR_RUNNING) {
2460 // request was cancelled, continue
2461 } else {
2462 ShouldNotReachHere();
2463 }
2464
2465 resume_clear_context(osthread);
2466 } else if (current == os::SuspendResume::SR_RUNNING) {
2467 // request was cancelled, continue
2468 } else if (current == os::SuspendResume::SR_WAKEUP_REQUEST) {
2469 // ignore
2470 } else {
2471 // ignore
2472 }
2473
2474 errno = old_errno;
2475 }
2476
2477
2478 static int SR_initialize() {
2479 struct sigaction act;
2480 char *s;
2481 // Get signal number to use for suspend/resume
2482 if ((s = ::getenv("_JAVA_SR_SIGNUM")) != 0) {
2483 int sig = ::strtol(s, 0, 10);
2484 if (sig > MAX2(SIGSEGV, SIGBUS) && // See 4355769.
2485 sig < NSIG) { // Must be legal signal and fit into sigflags[].
2486 SR_signum = sig;
2487 } else {
2488 warning("You set _JAVA_SR_SIGNUM=%d. It must be in range [%d, %d]. Using %d instead.",
2489 sig, MAX2(SIGSEGV, SIGBUS)+1, NSIG-1, SR_signum);
2490 }
2491 }
2492
2493 assert(SR_signum > SIGSEGV && SR_signum > SIGBUS,
2494 "SR_signum must be greater than max(SIGSEGV, SIGBUS), see 4355769");
2495
2496 sigemptyset(&SR_sigset);
2497 sigaddset(&SR_sigset, SR_signum);
2498
2499 // Set up signal handler for suspend/resume
2500 act.sa_flags = SA_RESTART|SA_SIGINFO;
2501 act.sa_handler = (void (*)(int)) SR_handler;
2502
2503 // SR_signum is blocked by default.
2504 // 4528190 - We also need to block pthread restart signal (32 on all
2505 // supported Bsd platforms). Note that BsdThreads need to block
2506 // this signal for all threads to work properly. So we don't have
2507 // to use hard-coded signal number when setting up the mask.
2508 pthread_sigmask(SIG_BLOCK, NULL, &act.sa_mask);
2509
2510 if (sigaction(SR_signum, &act, 0) == -1) {
2511 return -1;
2512 }
2513
2514 // Save signal flag
2515 os::Bsd::set_our_sigflags(SR_signum, act.sa_flags);
2516 return 0;
2517 }
2518
2519 static int sr_notify(OSThread* osthread) {
2520 int status = pthread_kill(osthread->pthread_id(), SR_signum);
2521 assert_status(status == 0, status, "pthread_kill");
2522 return status;
2523 }
2524
2525 // "Randomly" selected value for how long we want to spin
2526 // before bailing out on suspending a thread, also how often
2527 // we send a signal to a thread we want to resume
2528 static const int RANDOMLY_LARGE_INTEGER = 1000000;
2529 static const int RANDOMLY_LARGE_INTEGER2 = 100;
2530
2531 // returns true on success and false on error - really an error is fatal
2532 // but this seems the normal response to library errors
2533 static bool do_suspend(OSThread* osthread) {
2534 assert(osthread->sr.is_running(), "thread should be running");
2535 assert(!sr_semaphore.trywait(), "semaphore has invalid state");
2536
2537 // mark as suspended and send signal
2538 if (osthread->sr.request_suspend() != os::SuspendResume::SR_SUSPEND_REQUEST) {
2539 // failed to switch, state wasn't running?
2540 ShouldNotReachHere();
2541 return false;
2542 }
2543
2544 if (sr_notify(osthread) != 0) {
2545 ShouldNotReachHere();
2546 }
2547
2548 // managed to send the signal and switch to SUSPEND_REQUEST, now wait for SUSPENDED
2549 while (true) {
2550 if (sr_semaphore.timedwait(2)) {
2551 break;
2552 } else {
2553 // timeout
2554 os::SuspendResume::State cancelled = osthread->sr.cancel_suspend();
2555 if (cancelled == os::SuspendResume::SR_RUNNING) {
2556 return false;
2557 } else if (cancelled == os::SuspendResume::SR_SUSPENDED) {
2558 // make sure that we consume the signal on the semaphore as well
2559 sr_semaphore.wait();
2560 break;
2561 } else {
2562 ShouldNotReachHere();
2563 return false;
2564 }
2565 }
2566 }
2567
2568 guarantee(osthread->sr.is_suspended(), "Must be suspended");
2569 return true;
2570 }
2571
2572 static void do_resume(OSThread* osthread) {
2573 assert(osthread->sr.is_suspended(), "thread should be suspended");
2574 assert(!sr_semaphore.trywait(), "invalid semaphore state");
2575
2576 if (osthread->sr.request_wakeup() != os::SuspendResume::SR_WAKEUP_REQUEST) {
2577 // failed to switch to WAKEUP_REQUEST
2578 ShouldNotReachHere();
2579 return;
2580 }
2581
2582 while (true) {
2583 if (sr_notify(osthread) == 0) {
2584 if (sr_semaphore.timedwait(2)) {
2585 if (osthread->sr.is_running()) {
2586 return;
2587 }
2588 }
2589 } else {
2590 ShouldNotReachHere();
2591 }
2592 }
2593
2594 guarantee(osthread->sr.is_running(), "Must be running!");
2595 }
2596
2597 ///////////////////////////////////////////////////////////////////////////////////
2598 // signal handling (except suspend/resume)
2599
2600 // This routine may be used by user applications as a "hook" to catch signals.
2601 // The user-defined signal handler must pass unrecognized signals to this
2602 // routine, and if it returns true (non-zero), then the signal handler must
2603 // return immediately. If the flag "abort_if_unrecognized" is true, then this
2604 // routine will never retun false (zero), but instead will execute a VM panic
2605 // routine kill the process.
2606 //
2607 // If this routine returns false, it is OK to call it again. This allows
2608 // the user-defined signal handler to perform checks either before or after
2609 // the VM performs its own checks. Naturally, the user code would be making
2610 // a serious error if it tried to handle an exception (such as a null check
2611 // or breakpoint) that the VM was generating for its own correct operation.
2612 //
2613 // This routine may recognize any of the following kinds of signals:
2614 // SIGBUS, SIGSEGV, SIGILL, SIGFPE, SIGQUIT, SIGPIPE, SIGXFSZ, SIGUSR1.
2615 // It should be consulted by handlers for any of those signals.
2616 //
2617 // The caller of this routine must pass in the three arguments supplied
2618 // to the function referred to in the "sa_sigaction" (not the "sa_handler")
2619 // field of the structure passed to sigaction(). This routine assumes that
2620 // the sa_flags field passed to sigaction() includes SA_SIGINFO and SA_RESTART.
2621 //
2622 // Note that the VM will print warnings if it detects conflicting signal
2623 // handlers, unless invoked with the option "-XX:+AllowUserSignalHandlers".
2624 //
2625 extern "C" JNIEXPORT int JVM_handle_bsd_signal(int signo, siginfo_t* siginfo,
2626 void* ucontext,
2627 int abort_if_unrecognized);
2628
2629 static void signalHandler(int sig, siginfo_t* info, void* uc) {
2630 assert(info != NULL && uc != NULL, "it must be old kernel");
2631 int orig_errno = errno; // Preserve errno value over signal handler.
2632 JVM_handle_bsd_signal(sig, info, uc, true);
2633 errno = orig_errno;
2634 }
2635
2636
2637 // This boolean allows users to forward their own non-matching signals
2638 // to JVM_handle_bsd_signal, harmlessly.
2639 bool os::Bsd::signal_handlers_are_installed = false;
2640
2641 // For signal-chaining
2642 bool os::Bsd::libjsig_is_loaded = false;
2643 typedef struct sigaction *(*get_signal_t)(int);
2644 get_signal_t os::Bsd::get_signal_action = NULL;
2645
2646 struct sigaction* os::Bsd::get_chained_signal_action(int sig) {
2647 struct sigaction *actp = NULL;
2648
2649 if (libjsig_is_loaded) {
2650 // Retrieve the old signal handler from libjsig
2651 actp = (*get_signal_action)(sig);
2652 }
2653 if (actp == NULL) {
2654 // Retrieve the preinstalled signal handler from jvm
2655 actp = os::Posix::get_preinstalled_handler(sig);
2656 }
2657
2658 return actp;
2659 }
2660
2661 static bool call_chained_handler(struct sigaction *actp, int sig,
2662 siginfo_t *siginfo, void *context) {
2663 // Call the old signal handler
2664 if (actp->sa_handler == SIG_DFL) {
2665 // It's more reasonable to let jvm treat it as an unexpected exception
2666 // instead of taking the default action.
2667 return false;
2668 } else if (actp->sa_handler != SIG_IGN) {
2669 if ((actp->sa_flags & SA_NODEFER) == 0) {
2670 // automaticlly block the signal
2671 sigaddset(&(actp->sa_mask), sig);
2672 }
2673
2674 sa_handler_t hand;
2675 sa_sigaction_t sa;
2676 bool siginfo_flag_set = (actp->sa_flags & SA_SIGINFO) != 0;
2677 // retrieve the chained handler
2678 if (siginfo_flag_set) {
2679 sa = actp->sa_sigaction;
2680 } else {
2681 hand = actp->sa_handler;
2682 }
2683
2684 if ((actp->sa_flags & SA_RESETHAND) != 0) {
2685 actp->sa_handler = SIG_DFL;
2686 }
2687
2688 // try to honor the signal mask
2689 sigset_t oset;
2690 pthread_sigmask(SIG_SETMASK, &(actp->sa_mask), &oset);
2691
2692 // call into the chained handler
2693 if (siginfo_flag_set) {
2694 (*sa)(sig, siginfo, context);
2695 } else {
2696 (*hand)(sig);
2697 }
2698
2699 // restore the signal mask
2700 pthread_sigmask(SIG_SETMASK, &oset, 0);
2701 }
2702 // Tell jvm's signal handler the signal is taken care of.
2703 return true;
2704 }
2705
2706 bool os::Bsd::chained_handler(int sig, siginfo_t* siginfo, void* context) {
2707 bool chained = false;
2708 // signal-chaining
2709 if (UseSignalChaining) {
2710 struct sigaction *actp = get_chained_signal_action(sig);
2711 if (actp != NULL) {
2712 chained = call_chained_handler(actp, sig, siginfo, context);
2713 }
2714 }
2715 return chained;
2716 }
2717
2718 // for diagnostic
2719 int sigflags[NSIG];
2720
2721 int os::Bsd::get_our_sigflags(int sig) {
2722 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2723 return sigflags[sig];
2724 }
2725
2726 void os::Bsd::set_our_sigflags(int sig, int flags) {
2727 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2728 if (sig > 0 && sig < NSIG) {
2729 sigflags[sig] = flags;
2730 }
2731 }
2732
2733 void os::Bsd::set_signal_handler(int sig, bool set_installed) {
2734 // Check for overwrite.
2735 struct sigaction oldAct;
2736 sigaction(sig, (struct sigaction*)NULL, &oldAct);
2737
2738 void* oldhand = oldAct.sa_sigaction
2739 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2740 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2741 if (oldhand != CAST_FROM_FN_PTR(void*, SIG_DFL) &&
2742 oldhand != CAST_FROM_FN_PTR(void*, SIG_IGN) &&
2743 oldhand != CAST_FROM_FN_PTR(void*, (sa_sigaction_t)signalHandler)) {
2744 if (AllowUserSignalHandlers || !set_installed) {
2745 // Do not overwrite; user takes responsibility to forward to us.
2746 return;
2747 } else if (UseSignalChaining) {
2748 // save the old handler in jvm
2749 os::Posix::save_preinstalled_handler(sig, oldAct);
2750 // libjsig also interposes the sigaction() call below and saves the
2751 // old sigaction on it own.
2752 } else {
2753 fatal("Encountered unexpected pre-existing sigaction handler "
2754 "%#lx for signal %d.", (long)oldhand, sig);
2755 }
2756 }
2757
2758 struct sigaction sigAct;
2759 sigfillset(&(sigAct.sa_mask));
2760 sigAct.sa_handler = SIG_DFL;
2761 if (!set_installed) {
2762 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2763 } else {
2764 sigAct.sa_sigaction = signalHandler;
2765 sigAct.sa_flags = SA_SIGINFO|SA_RESTART;
2766 }
2767 #ifdef __APPLE__
2768 // Needed for main thread as XNU (Mac OS X kernel) will only deliver SIGSEGV
2769 // (which starts as SIGBUS) on main thread with faulting address inside "stack+guard pages"
2770 // if the signal handler declares it will handle it on alternate stack.
2771 // Notice we only declare we will handle it on alt stack, but we are not
2772 // actually going to use real alt stack - this is just a workaround.
2773 // Please see ux_exception.c, method catch_mach_exception_raise for details
2774 // link http://www.opensource.apple.com/source/xnu/xnu-2050.18.24/bsd/uxkern/ux_exception.c
2775 if (sig == SIGSEGV) {
2776 sigAct.sa_flags |= SA_ONSTACK;
2777 }
2778 #endif
2779
2780 // Save flags, which are set by ours
2781 assert(sig > 0 && sig < NSIG, "vm signal out of expected range");
2782 sigflags[sig] = sigAct.sa_flags;
2783
2784 int ret = sigaction(sig, &sigAct, &oldAct);
2785 assert(ret == 0, "check");
2786
2787 void* oldhand2 = oldAct.sa_sigaction
2788 ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
2789 : CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
2790 assert(oldhand2 == oldhand, "no concurrent signal handler installation");
2791 }
2792
2793 // install signal handlers for signals that HotSpot needs to
2794 // handle in order to support Java-level exception handling.
2795
2796 void os::Bsd::install_signal_handlers() {
2797 if (!signal_handlers_are_installed) {
2798 signal_handlers_are_installed = true;
2799
2800 // signal-chaining
2801 typedef void (*signal_setting_t)();
2802 signal_setting_t begin_signal_setting = NULL;
2803 signal_setting_t end_signal_setting = NULL;
2804 begin_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2805 dlsym(RTLD_DEFAULT, "JVM_begin_signal_setting"));
2806 if (begin_signal_setting != NULL) {
2807 end_signal_setting = CAST_TO_FN_PTR(signal_setting_t,
2808 dlsym(RTLD_DEFAULT, "JVM_end_signal_setting"));
2809 get_signal_action = CAST_TO_FN_PTR(get_signal_t,
2810 dlsym(RTLD_DEFAULT, "JVM_get_signal_action"));
2811 libjsig_is_loaded = true;
2812 assert(UseSignalChaining, "should enable signal-chaining");
2813 }
2814 if (libjsig_is_loaded) {
2815 // Tell libjsig jvm is setting signal handlers
2816 (*begin_signal_setting)();
2817 }
2818
2819 set_signal_handler(SIGSEGV, true);
2820 set_signal_handler(SIGPIPE, true);
2821 set_signal_handler(SIGBUS, true);
2822 set_signal_handler(SIGILL, true);
2823 set_signal_handler(SIGFPE, true);
2824 set_signal_handler(SIGXFSZ, true);
2825
2826 #if defined(__APPLE__)
2827 // In Mac OS X 10.4, CrashReporter will write a crash log for all 'fatal' signals, including
2828 // signals caught and handled by the JVM. To work around this, we reset the mach task
2829 // signal handler that's placed on our process by CrashReporter. This disables
2830 // CrashReporter-based reporting.
2831 //
2832 // This work-around is not necessary for 10.5+, as CrashReporter no longer intercedes
2833 // on caught fatal signals.
2834 //
2835 // Additionally, gdb installs both standard BSD signal handlers, and mach exception
2836 // handlers. By replacing the existing task exception handler, we disable gdb's mach
2837 // exception handling, while leaving the standard BSD signal handlers functional.
2838 kern_return_t kr;
2839 kr = task_set_exception_ports(mach_task_self(),
2840 EXC_MASK_BAD_ACCESS | EXC_MASK_ARITHMETIC,
2841 MACH_PORT_NULL,
2842 EXCEPTION_STATE_IDENTITY,
2843 MACHINE_THREAD_STATE);
2844
2845 assert(kr == KERN_SUCCESS, "could not set mach task signal handler");
2846 #endif
2847
2848 if (libjsig_is_loaded) {
2849 // Tell libjsig jvm finishes setting signal handlers
2850 (*end_signal_setting)();
2851 }
2852
2853 // We don't activate signal checker if libjsig is in place, we trust ourselves
2854 // and if UserSignalHandler is installed all bets are off
2855 if (CheckJNICalls) {
2856 if (libjsig_is_loaded) {
2857 log_debug(jni, resolve)("Info: libjsig is activated, all active signal checking is disabled");
2858 check_signals = false;
2859 }
2860 if (AllowUserSignalHandlers) {
2861 log_debug(jni, resolve)("Info: AllowUserSignalHandlers is activated, all active signal checking is disabled");
2862 check_signals = false;
2863 }
2864 }
2865 }
2866 }
2867
2868
2869 /////
2870 // glibc on Bsd platform uses non-documented flag
2871 // to indicate, that some special sort of signal
2872 // trampoline is used.
2873 // We will never set this flag, and we should
2874 // ignore this flag in our diagnostic
2875 #ifdef SIGNIFICANT_SIGNAL_MASK
2876 #undef SIGNIFICANT_SIGNAL_MASK
2877 #endif
2878 #define SIGNIFICANT_SIGNAL_MASK (~0x04000000)
2879
2880 static const char* get_signal_handler_name(address handler,
2881 char* buf, int buflen) {
2882 int offset;
2883 bool found = os::dll_address_to_library_name(handler, buf, buflen, &offset);
2884 if (found) {
2885 // skip directory names
2886 const char *p1, *p2;
2887 p1 = buf;
2888 size_t len = strlen(os::file_separator());
2889 while ((p2 = strstr(p1, os::file_separator())) != NULL) p1 = p2 + len;
2890 jio_snprintf(buf, buflen, "%s+0x%x", p1, offset);
2891 } else {
2892 jio_snprintf(buf, buflen, PTR_FORMAT, handler);
2893 }
2894 return buf;
2895 }
2896
2897 static void print_signal_handler(outputStream* st, int sig,
2898 char* buf, size_t buflen) {
2899 struct sigaction sa;
2900
2901 sigaction(sig, NULL, &sa);
2902
2903 // See comment for SIGNIFICANT_SIGNAL_MASK define
2904 sa.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
2905
2906 st->print("%s: ", os::exception_name(sig, buf, buflen));
2907
2908 address handler = (sa.sa_flags & SA_SIGINFO)
2909 ? CAST_FROM_FN_PTR(address, sa.sa_sigaction)
2910 : CAST_FROM_FN_PTR(address, sa.sa_handler);
2911
2912 if (handler == CAST_FROM_FN_PTR(address, SIG_DFL)) {
2913 st->print("SIG_DFL");
2914 } else if (handler == CAST_FROM_FN_PTR(address, SIG_IGN)) {
2915 st->print("SIG_IGN");
2916 } else {
2917 st->print("[%s]", get_signal_handler_name(handler, buf, buflen));
2918 }
2919
2920 st->print(", sa_mask[0]=");
2921 os::Posix::print_signal_set_short(st, &sa.sa_mask);
2922
2923 address rh = VMError::get_resetted_sighandler(sig);
2924 // May be, handler was resetted by VMError?
2925 if (rh != NULL) {
2926 handler = rh;
2927 sa.sa_flags = VMError::get_resetted_sigflags(sig) & SIGNIFICANT_SIGNAL_MASK;
2928 }
2929
2930 st->print(", sa_flags=");
2931 os::Posix::print_sa_flags(st, sa.sa_flags);
2932
2933 // Check: is it our handler?
2934 if (handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler) ||
2935 handler == CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler)) {
2936 // It is our signal handler
2937 // check for flags, reset system-used one!
2938 if ((int)sa.sa_flags != os::Bsd::get_our_sigflags(sig)) {
2939 st->print(
2940 ", flags was changed from " PTR32_FORMAT ", consider using jsig library",
2941 os::Bsd::get_our_sigflags(sig));
2942 }
2943 }
2944 st->cr();
2945 }
2946
2947
2948 #define DO_SIGNAL_CHECK(sig) \
2949 do { \
2950 if (!sigismember(&check_signal_done, sig)) { \
2951 os::Bsd::check_signal_handler(sig); \
2952 } \
2953 } while (0)
2954
2955 // This method is a periodic task to check for misbehaving JNI applications
2956 // under CheckJNI, we can add any periodic checks here
2957
2958 void os::run_periodic_checks() {
2959
2960 if (check_signals == false) return;
2961
2962 // SEGV and BUS if overridden could potentially prevent
2963 // generation of hs*.log in the event of a crash, debugging
2964 // such a case can be very challenging, so we absolutely
2965 // check the following for a good measure:
2966 DO_SIGNAL_CHECK(SIGSEGV);
2967 DO_SIGNAL_CHECK(SIGILL);
2968 DO_SIGNAL_CHECK(SIGFPE);
2969 DO_SIGNAL_CHECK(SIGBUS);
2970 DO_SIGNAL_CHECK(SIGPIPE);
2971 DO_SIGNAL_CHECK(SIGXFSZ);
2972
2973
2974 // ReduceSignalUsage allows the user to override these handlers
2975 // see comments at the very top and jvm_md.h
2976 if (!ReduceSignalUsage) {
2977 DO_SIGNAL_CHECK(SHUTDOWN1_SIGNAL);
2978 DO_SIGNAL_CHECK(SHUTDOWN2_SIGNAL);
2979 DO_SIGNAL_CHECK(SHUTDOWN3_SIGNAL);
2980 DO_SIGNAL_CHECK(BREAK_SIGNAL);
2981 }
2982
2983 DO_SIGNAL_CHECK(SR_signum);
2984 }
2985
2986 typedef int (*os_sigaction_t)(int, const struct sigaction *, struct sigaction *);
2987
2988 static os_sigaction_t os_sigaction = NULL;
2989
2990 void os::Bsd::check_signal_handler(int sig) {
2991 char buf[O_BUFLEN];
2992 address jvmHandler = NULL;
2993
2994
2995 struct sigaction act;
2996 if (os_sigaction == NULL) {
2997 // only trust the default sigaction, in case it has been interposed
2998 os_sigaction = (os_sigaction_t)dlsym(RTLD_DEFAULT, "sigaction");
2999 if (os_sigaction == NULL) return;
3000 }
3001
3002 os_sigaction(sig, (struct sigaction*)NULL, &act);
3003
3004
3005 act.sa_flags &= SIGNIFICANT_SIGNAL_MASK;
3006
3007 address thisHandler = (act.sa_flags & SA_SIGINFO)
3008 ? CAST_FROM_FN_PTR(address, act.sa_sigaction)
3009 : CAST_FROM_FN_PTR(address, act.sa_handler);
3010
3011
3012 switch (sig) {
3013 case SIGSEGV:
3014 case SIGBUS:
3015 case SIGFPE:
3016 case SIGPIPE:
3017 case SIGILL:
3018 case SIGXFSZ:
3019 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)signalHandler);
3020 break;
3021
3022 case SHUTDOWN1_SIGNAL:
3023 case SHUTDOWN2_SIGNAL:
3024 case SHUTDOWN3_SIGNAL:
3025 case BREAK_SIGNAL:
3026 jvmHandler = (address)user_handler();
3027 break;
3028
3029 default:
3030 if (sig == SR_signum) {
3031 jvmHandler = CAST_FROM_FN_PTR(address, (sa_sigaction_t)SR_handler);
3032 } else {
3033 return;
3034 }
3035 break;
3036 }
3037
3038 if (thisHandler != jvmHandler) {
3039 tty->print("Warning: %s handler ", exception_name(sig, buf, O_BUFLEN));
3040 tty->print("expected:%s", get_signal_handler_name(jvmHandler, buf, O_BUFLEN));
3041 tty->print_cr(" found:%s", get_signal_handler_name(thisHandler, buf, O_BUFLEN));
3042 // No need to check this sig any longer
3043 sigaddset(&check_signal_done, sig);
3044 // Running under non-interactive shell, SHUTDOWN2_SIGNAL will be reassigned SIG_IGN
3045 if (sig == SHUTDOWN2_SIGNAL && !isatty(fileno(stdin))) {
3046 tty->print_cr("Running in non-interactive shell, %s handler is replaced by shell",
3047 exception_name(sig, buf, O_BUFLEN));
3048 }
3049 } else if(os::Bsd::get_our_sigflags(sig) != 0 && (int)act.sa_flags != os::Bsd::get_our_sigflags(sig)) {
3050 tty->print("Warning: %s handler flags ", exception_name(sig, buf, O_BUFLEN));
3051 tty->print("expected:");
3052 os::Posix::print_sa_flags(tty, os::Bsd::get_our_sigflags(sig));
3053 tty->cr();
3054 tty->print(" found:");
3055 os::Posix::print_sa_flags(tty, act.sa_flags);
3056 tty->cr();
3057 // No need to check this sig any longer
3058 sigaddset(&check_signal_done, sig);
3059 }
3060
3061 // Dump all the signal
3062 if (sigismember(&check_signal_done, sig)) {
3063 print_signal_handlers(tty, buf, O_BUFLEN);
3064 }
3065 }
3066
3067 extern void report_error(char* file_name, int line_no, char* title,
3068 char* format, ...);
3069
3070 // this is called _before_ the most of global arguments have been parsed
3071 void os::init(void) {
3072 char dummy; // used to get a guess on initial stack address
3073
3074 clock_tics_per_sec = CLK_TCK;
3075
3076 init_random(1234567);
3077
3078 Bsd::set_page_size(getpagesize());
3079 if (Bsd::page_size() == -1) {
3080 fatal("os_bsd.cpp: os::init: sysconf failed (%s)", os::strerror(errno));
3081 }
3082 init_page_sizes((size_t) Bsd::page_size());
3083
3084 Bsd::initialize_system_info();
3085
3086 // _main_thread points to the thread that created/loaded the JVM.
3087 Bsd::_main_thread = pthread_self();
3088
3089 Bsd::clock_init();
3090 initial_time_count = javaTimeNanos();
3091
3092 os::Posix::init();
3093 }
3094
3095 // To install functions for atexit system call
3096 extern "C" {
3097 static void perfMemory_exit_helper() {
3098 perfMemory_exit();
3099 }
3100 }
3101
3102 // this is called _after_ the global arguments have been parsed
3103 jint os::init_2(void) {
3104
3105 // This could be set after os::Posix::init() but all platforms
3106 // have to set it the same so we have to mirror Solaris.
3107 DEBUG_ONLY(os::set_mutex_init_done();)
3108
3109 os::Posix::init_2();
3110
3111 // initialize suspend/resume support - must do this before signal_sets_init()
3112 if (SR_initialize() != 0) {
3113 perror("SR_initialize failed");
3114 return JNI_ERR;
3115 }
3116
3117 Bsd::signal_sets_init();
3118 Bsd::install_signal_handlers();
3119 // Initialize data for jdk.internal.misc.Signal
3120 if (!ReduceSignalUsage) {
3121 jdk_misc_signal_init();
3122 }
3123
3124 // Check and sets minimum stack sizes against command line options
3125 if (Posix::set_minimum_stack_sizes() == JNI_ERR) {
3126 return JNI_ERR;
3127 }
3128
3129 if (MaxFDLimit) {
3130 // set the number of file descriptors to max. print out error
3131 // if getrlimit/setrlimit fails but continue regardless.
3132 struct rlimit nbr_files;
3133 int status = getrlimit(RLIMIT_NOFILE, &nbr_files);
3134 if (status != 0) {
3135 log_info(os)("os::init_2 getrlimit failed: %s", os::strerror(errno));
3136 } else {
3137 nbr_files.rlim_cur = nbr_files.rlim_max;
3138
3139 #ifdef __APPLE__
3140 // Darwin returns RLIM_INFINITY for rlim_max, but fails with EINVAL if
3141 // you attempt to use RLIM_INFINITY. As per setrlimit(2), OPEN_MAX must
3142 // be used instead
3143 nbr_files.rlim_cur = MIN(OPEN_MAX, nbr_files.rlim_cur);
3144 #endif
3145
3146 status = setrlimit(RLIMIT_NOFILE, &nbr_files);
3147 if (status != 0) {
3148 log_info(os)("os::init_2 setrlimit failed: %s", os::strerror(errno));
3149 }
3150 }
3151 }
3152
3153 // at-exit methods are called in the reverse order of their registration.
3154 // atexit functions are called on return from main or as a result of a
3155 // call to exit(3C). There can be only 32 of these functions registered
3156 // and atexit() does not set errno.
3157
3158 if (PerfAllowAtExitRegistration) {
3159 // only register atexit functions if PerfAllowAtExitRegistration is set.
3160 // atexit functions can be delayed until process exit time, which
3161 // can be problematic for embedded VM situations. Embedded VMs should
3162 // call DestroyJavaVM() to assure that VM resources are released.
3163
3164 // note: perfMemory_exit_helper atexit function may be removed in
3165 // the future if the appropriate cleanup code can be added to the
3166 // VM_Exit VMOperation's doit method.
3167 if (atexit(perfMemory_exit_helper) != 0) {
3168 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
3169 }
3170 }
3171
3172 // initialize thread priority policy
3173 prio_init();
3174
3175 #ifdef __APPLE__
3176 // dynamically link to objective c gc registration
3177 void *handleLibObjc = dlopen(OBJC_LIB, RTLD_LAZY);
3178 if (handleLibObjc != NULL) {
3179 objc_registerThreadWithCollectorFunction = (objc_registerThreadWithCollector_t) dlsym(handleLibObjc, OBJC_GCREGISTER);
3180 }
3181 #endif
3182
3183 return JNI_OK;
3184 }
3185
3186 int os::active_processor_count() {
3187 // User has overridden the number of active processors
3188 if (ActiveProcessorCount > 0) {
3189 log_trace(os)("active_processor_count: "
3190 "active processor count set by user : %d",
3191 ActiveProcessorCount);
3192 return ActiveProcessorCount;
3193 }
3194
3195 return _processor_count;
3196 }
3197
3198 #ifdef __APPLE__
3199 static volatile int* volatile apic_to_processor_mapping = NULL;
3200 static volatile int next_processor_id = 0;
3201
3202 static inline volatile int* get_apic_to_processor_mapping() {
3203 volatile int* mapping = Atomic::load_acquire(&apic_to_processor_mapping);
3204 if (mapping == NULL) {
3205 // Calculate possible number space for APIC ids. This space is not necessarily
3206 // in the range [0, number_of_processors).
3207 uint total_bits = 0;
3208 for (uint i = 0;; ++i) {
3209 uint eax = 0xb; // Query topology leaf
3210 uint ebx;
3211 uint ecx = i;
3212 uint edx;
3213
3214 __asm__ ("cpuid\n\t" : "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx) : );
3215
3216 uint level_type = (ecx >> 8) & 0xFF;
3217 if (level_type == 0) {
3218 // Invalid level; end of topology
3219 break;
3220 }
3221 uint level_apic_id_shift = eax & ((1u << 5) - 1);
3222 total_bits += level_apic_id_shift;
3223 }
3224
3225 uint max_apic_ids = 1u << total_bits;
3226 mapping = NEW_C_HEAP_ARRAY(int, max_apic_ids, mtInternal);
3227
3228 for (uint i = 0; i < max_apic_ids; ++i) {
3229 mapping[i] = -1;
3230 }
3231
3232 if (!Atomic::replace_if_null(&apic_to_processor_mapping, mapping)) {
3233 FREE_C_HEAP_ARRAY(int, mapping);
3234 mapping = Atomic::load_acquire(&apic_to_processor_mapping);
3235 }
3236 }
3237
3238 return mapping;
3239 }
3240
3241 uint os::processor_id() {
3242 volatile int* mapping = get_apic_to_processor_mapping();
3243
3244 uint eax = 0xb;
3245 uint ebx;
3246 uint ecx = 0;
3247 uint edx;
3248
3249 __asm__ ("cpuid\n\t" : "+a" (eax), "+b" (ebx), "+c" (ecx), "+d" (edx) : );
3250
3251 // Map from APIC id to a unique logical processor ID in the expected
3252 // [0, num_processors) range.
3253
3254 uint apic_id = edx;
3255 int processor_id = Atomic::load(&mapping[apic_id]);
3256
3257 while (processor_id < 0) {
3258 if (Atomic::cmpxchg(&mapping[apic_id], -1, -2) == -1) {
3259 Atomic::store(&mapping[apic_id], Atomic::add(&next_processor_id, 1) - 1);
3260 }
3261 processor_id = Atomic::load(&mapping[apic_id]);
3262 }
3263
3264 assert(processor_id >= 0 && processor_id < os::processor_count(), "invalid processor id");
3265
3266 return (uint)processor_id;
3267 }
3268 #endif
3269
3270 void os::set_native_thread_name(const char *name) {
3271 #if defined(__APPLE__) && MAC_OS_X_VERSION_MIN_REQUIRED > MAC_OS_X_VERSION_10_5
3272 // This is only supported in Snow Leopard and beyond
3273 if (name != NULL) {
3274 // Add a "Java: " prefix to the name
3275 char buf[MAXTHREADNAMESIZE];
3276 snprintf(buf, sizeof(buf), "Java: %s", name);
3277 pthread_setname_np(buf);
3278 }
3279 #endif
3280 }
3281
3282 bool os::bind_to_processor(uint processor_id) {
3283 // Not yet implemented.
3284 return false;
3285 }
3286
3287 void os::SuspendedThreadTask::internal_do_task() {
3288 if (do_suspend(_thread->osthread())) {
3289 SuspendedThreadTaskContext context(_thread, _thread->osthread()->ucontext());
3290 do_task(context);
3291 do_resume(_thread->osthread());
3292 }
3293 }
3294
3295 ////////////////////////////////////////////////////////////////////////////////
3296 // debug support
3297
3298 bool os::find(address addr, outputStream* st) {
3299 Dl_info dlinfo;
3300 memset(&dlinfo, 0, sizeof(dlinfo));
3301 if (dladdr(addr, &dlinfo) != 0) {
3302 st->print(INTPTR_FORMAT ": ", (intptr_t)addr);
3303 if (dlinfo.dli_sname != NULL && dlinfo.dli_saddr != NULL) {
3304 st->print("%s+%#x", dlinfo.dli_sname,
3305 (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_saddr));
3306 } else if (dlinfo.dli_fbase != NULL) {
3307 st->print("<offset %#x>", (uint)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase));
3308 } else {
3309 st->print("<absolute address>");
3310 }
3311 if (dlinfo.dli_fname != NULL) {
3312 st->print(" in %s", dlinfo.dli_fname);
3313 }
3314 if (dlinfo.dli_fbase != NULL) {
3315 st->print(" at " INTPTR_FORMAT, (intptr_t)dlinfo.dli_fbase);
3316 }
3317 st->cr();
3318
3319 if (Verbose) {
3320 // decode some bytes around the PC
3321 address begin = clamp_address_in_page(addr-40, addr, os::vm_page_size());
3322 address end = clamp_address_in_page(addr+40, addr, os::vm_page_size());
3323 address lowest = (address) dlinfo.dli_sname;
3324 if (!lowest) lowest = (address) dlinfo.dli_fbase;
3325 if (begin < lowest) begin = lowest;
3326 Dl_info dlinfo2;
3327 if (dladdr(end, &dlinfo2) != 0 && dlinfo2.dli_saddr != dlinfo.dli_saddr
3328 && end > dlinfo2.dli_saddr && dlinfo2.dli_saddr > begin) {
3329 end = (address) dlinfo2.dli_saddr;
3330 }
3331 Disassembler::decode(begin, end, st);
3332 }
3333 return true;
3334 }
3335 return false;
3336 }
3337
3338 ////////////////////////////////////////////////////////////////////////////////
3339 // misc
3340
3341 // This does not do anything on Bsd. This is basically a hook for being
3342 // able to use structured exception handling (thread-local exception filters)
3343 // on, e.g., Win32.
3344 void os::os_exception_wrapper(java_call_t f, JavaValue* value,
3345 const methodHandle& method, JavaCallArguments* args,
3346 Thread* thread) {
3347 f(value, method, args, thread);
3348 }
3349
3350 void os::print_statistics() {
3351 }
3352
3353 bool os::message_box(const char* title, const char* message) {
3354 int i;
3355 fdStream err(defaultStream::error_fd());
3356 for (i = 0; i < 78; i++) err.print_raw("=");
3357 err.cr();
3358 err.print_raw_cr(title);
3359 for (i = 0; i < 78; i++) err.print_raw("-");
3360 err.cr();
3361 err.print_raw_cr(message);
3362 for (i = 0; i < 78; i++) err.print_raw("=");
3363 err.cr();
3364
3365 char buf[16];
3366 // Prevent process from exiting upon "read error" without consuming all CPU
3367 while (::read(0, buf, sizeof(buf)) <= 0) { ::sleep(100); }
3368
3369 return buf[0] == 'y' || buf[0] == 'Y';
3370 }
3371
3372 static inline struct timespec get_mtime(const char* filename) {
3373 struct stat st;
3374 int ret = os::stat(filename, &st);
3375 assert(ret == 0, "failed to stat() file '%s': %s", filename, os::strerror(errno));
3376 #ifdef __APPLE__
3377 return st.st_mtimespec;
3378 #else
3379 return st.st_mtim;
3380 #endif
3381 }
3382
3383 int os::compare_file_modified_times(const char* file1, const char* file2) {
3384 struct timespec filetime1 = get_mtime(file1);
3385 struct timespec filetime2 = get_mtime(file2);
3386 int diff = filetime1.tv_sec - filetime2.tv_sec;
3387 if (diff == 0) {
3388 return filetime1.tv_nsec - filetime2.tv_nsec;
3389 }
3390 return diff;
3391 }
3392
3393 // Is a (classpath) directory empty?
3394 bool os::dir_is_empty(const char* path) {
3395 DIR *dir = NULL;
3396 struct dirent *ptr;
3397
3398 dir = opendir(path);
3399 if (dir == NULL) return true;
3400
3401 // Scan the directory
3402 bool result = true;
3403 while (result && (ptr = readdir(dir)) != NULL) {
3404 if (strcmp(ptr->d_name, ".") != 0 && strcmp(ptr->d_name, "..") != 0) {
3405 result = false;
3406 }
3407 }
3408 closedir(dir);
3409 return result;
3410 }
3411
3412 // This code originates from JDK's sysOpen and open64_w
3413 // from src/solaris/hpi/src/system_md.c
3414
3415 int os::open(const char *path, int oflag, int mode) {
3416 if (strlen(path) > MAX_PATH - 1) {
3417 errno = ENAMETOOLONG;
3418 return -1;
3419 }
3420 int fd;
3421
3422 fd = ::open(path, oflag, mode);
3423 if (fd == -1) return -1;
3424
3425 // If the open succeeded, the file might still be a directory
3426 {
3427 struct stat buf;
3428 int ret = ::fstat(fd, &buf);
3429 int st_mode = buf.st_mode;
3430
3431 if (ret != -1) {
3432 if ((st_mode & S_IFMT) == S_IFDIR) {
3433 errno = EISDIR;
3434 ::close(fd);
3435 return -1;
3436 }
3437 } else {
3438 ::close(fd);
3439 return -1;
3440 }
3441 }
3442
3443 // All file descriptors that are opened in the JVM and not
3444 // specifically destined for a subprocess should have the
3445 // close-on-exec flag set. If we don't set it, then careless 3rd
3446 // party native code might fork and exec without closing all
3447 // appropriate file descriptors (e.g. as we do in closeDescriptors in
3448 // UNIXProcess.c), and this in turn might:
3449 //
3450 // - cause end-of-file to fail to be detected on some file
3451 // descriptors, resulting in mysterious hangs, or
3452 //
3453 // - might cause an fopen in the subprocess to fail on a system
3454 // suffering from bug 1085341.
3455 //
3456 // (Yes, the default setting of the close-on-exec flag is a Unix
3457 // design flaw)
3458 //
3459 // See:
3460 // 1085341: 32-bit stdio routines should support file descriptors >255
3461 // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
3462 // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
3463 //
3464 #ifdef FD_CLOEXEC
3465 {
3466 int flags = ::fcntl(fd, F_GETFD);
3467 if (flags != -1) {
3468 ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
3469 }
3470 }
3471 #endif
3472
3473 return fd;
3474 }
3475
3476
3477 // create binary file, rewriting existing file if required
3478 int os::create_binary_file(const char* path, bool rewrite_existing) {
3479 int oflags = O_WRONLY | O_CREAT;
3480 if (!rewrite_existing) {
3481 oflags |= O_EXCL;
3482 }
3483 return ::open(path, oflags, S_IREAD | S_IWRITE);
3484 }
3485
3486 // return current position of file pointer
3487 jlong os::current_file_offset(int fd) {
3488 return (jlong)::lseek(fd, (off_t)0, SEEK_CUR);
3489 }
3490
3491 // move file pointer to the specified offset
3492 jlong os::seek_to_file_offset(int fd, jlong offset) {
3493 return (jlong)::lseek(fd, (off_t)offset, SEEK_SET);
3494 }
3495
3496 // This code originates from JDK's sysAvailable
3497 // from src/solaris/hpi/src/native_threads/src/sys_api_td.c
3498
3499 int os::available(int fd, jlong *bytes) {
3500 jlong cur, end;
3501 int mode;
3502 struct stat buf;
3503
3504 if (::fstat(fd, &buf) >= 0) {
3505 mode = buf.st_mode;
3506 if (S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) {
3507 int n;
3508 if (::ioctl(fd, FIONREAD, &n) >= 0) {
3509 *bytes = n;
3510 return 1;
3511 }
3512 }
3513 }
3514 if ((cur = ::lseek(fd, 0L, SEEK_CUR)) == -1) {
3515 return 0;
3516 } else if ((end = ::lseek(fd, 0L, SEEK_END)) == -1) {
3517 return 0;
3518 } else if (::lseek(fd, cur, SEEK_SET) == -1) {
3519 return 0;
3520 }
3521 *bytes = end - cur;
3522 return 1;
3523 }
3524
3525 // Map a block of memory.
3526 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
3527 char *addr, size_t bytes, bool read_only,
3528 bool allow_exec) {
3529 int prot;
3530 int flags;
3531
3532 if (read_only) {
3533 prot = PROT_READ;
3534 flags = MAP_SHARED;
3535 } else {
3536 prot = PROT_READ | PROT_WRITE;
3537 flags = MAP_PRIVATE;
3538 }
3539
3540 if (allow_exec) {
3541 prot |= PROT_EXEC;
3542 }
3543
3544 if (addr != NULL) {
3545 flags |= MAP_FIXED;
3546 }
3547
3548 char* mapped_address = (char*)mmap(addr, (size_t)bytes, prot, flags,
3549 fd, file_offset);
3550 if (mapped_address == MAP_FAILED) {
3551 return NULL;
3552 }
3553 return mapped_address;
3554 }
3555
3556
3557 // Remap a block of memory.
3558 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
3559 char *addr, size_t bytes, bool read_only,
3560 bool allow_exec) {
3561 // same as map_memory() on this OS
3562 return os::map_memory(fd, file_name, file_offset, addr, bytes, read_only,
3563 allow_exec);
3564 }
3565
3566
3567 // Unmap a block of memory.
3568 bool os::pd_unmap_memory(char* addr, size_t bytes) {
3569 return munmap(addr, bytes) == 0;
3570 }
3571
3572 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
3573 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
3574 // of a thread.
3575 //
3576 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
3577 // the fast estimate available on the platform.
3578
3579 jlong os::current_thread_cpu_time() {
3580 #ifdef __APPLE__
3581 return os::thread_cpu_time(Thread::current(), true /* user + sys */);
3582 #else
3583 Unimplemented();
3584 return 0;
3585 #endif
3586 }
3587
3588 jlong os::thread_cpu_time(Thread* thread) {
3589 #ifdef __APPLE__
3590 return os::thread_cpu_time(thread, true /* user + sys */);
3591 #else
3592 Unimplemented();
3593 return 0;
3594 #endif
3595 }
3596
3597 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
3598 #ifdef __APPLE__
3599 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
3600 #else
3601 Unimplemented();
3602 return 0;
3603 #endif
3604 }
3605
3606 jlong os::thread_cpu_time(Thread *thread, bool user_sys_cpu_time) {
3607 #ifdef __APPLE__
3608 struct thread_basic_info tinfo;
3609 mach_msg_type_number_t tcount = THREAD_INFO_MAX;
3610 kern_return_t kr;
3611 thread_t mach_thread;
3612
3613 mach_thread = thread->osthread()->thread_id();
3614 kr = thread_info(mach_thread, THREAD_BASIC_INFO, (thread_info_t)&tinfo, &tcount);
3615 if (kr != KERN_SUCCESS) {
3616 return -1;
3617 }
3618
3619 if (user_sys_cpu_time) {
3620 jlong nanos;
3621 nanos = ((jlong) tinfo.system_time.seconds + tinfo.user_time.seconds) * (jlong)1000000000;
3622 nanos += ((jlong) tinfo.system_time.microseconds + (jlong) tinfo.user_time.microseconds) * (jlong)1000;
3623 return nanos;
3624 } else {
3625 return ((jlong)tinfo.user_time.seconds * 1000000000) + ((jlong)tinfo.user_time.microseconds * (jlong)1000);
3626 }
3627 #else
3628 Unimplemented();
3629 return 0;
3630 #endif
3631 }
3632
3633
3634 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3635 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3636 info_ptr->may_skip_backward = false; // elapsed time not wall time
3637 info_ptr->may_skip_forward = false; // elapsed time not wall time
3638 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3639 }
3640
3641 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
3642 info_ptr->max_value = ALL_64_BITS; // will not wrap in less than 64 bits
3643 info_ptr->may_skip_backward = false; // elapsed time not wall time
3644 info_ptr->may_skip_forward = false; // elapsed time not wall time
3645 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
3646 }
3647
3648 bool os::is_thread_cpu_time_supported() {
3649 #ifdef __APPLE__
3650 return true;
3651 #else
3652 return false;
3653 #endif
3654 }
3655
3656 // System loadavg support. Returns -1 if load average cannot be obtained.
3657 // Bsd doesn't yet have a (official) notion of processor sets,
3658 // so just return the system wide load average.
3659 int os::loadavg(double loadavg[], int nelem) {
3660 return ::getloadavg(loadavg, nelem);
3661 }
3662
3663 void os::pause() {
3664 char filename[MAX_PATH];
3665 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
3666 jio_snprintf(filename, MAX_PATH, "%s", PauseAtStartupFile);
3667 } else {
3668 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
3669 }
3670
3671 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
3672 if (fd != -1) {
3673 struct stat buf;
3674 ::close(fd);
3675 while (::stat(filename, &buf) == 0) {
3676 (void)::poll(NULL, 0, 100);
3677 }
3678 } else {
3679 jio_fprintf(stderr,
3680 "Could not open pause file '%s', continuing immediately.\n", filename);
3681 }
3682 }
3683
3684 // Darwin has no "environ" in a dynamic library.
3685 #ifdef __APPLE__
3686 #include <crt_externs.h>
3687 #define environ (*_NSGetEnviron())
3688 #else
3689 extern char** environ;
3690 #endif
3691
3692 // Run the specified command in a separate process. Return its exit value,
3693 // or -1 on failure (e.g. can't fork a new process).
3694 // Unlike system(), this function can be called from signal handler. It
3695 // doesn't block SIGINT et al.
3696 int os::fork_and_exec(char* cmd, bool use_vfork_if_available) {
3697 const char * argv[4] = {"sh", "-c", cmd, NULL};
3698
3699 // fork() in BsdThreads/NPTL is not async-safe. It needs to run
3700 // pthread_atfork handlers and reset pthread library. All we need is a
3701 // separate process to execve. Make a direct syscall to fork process.
3702 // On IA64 there's no fork syscall, we have to use fork() and hope for
3703 // the best...
3704 pid_t pid = fork();
3705
3706 if (pid < 0) {
3707 // fork failed
3708 return -1;
3709
3710 } else if (pid == 0) {
3711 // child process
3712
3713 // execve() in BsdThreads will call pthread_kill_other_threads_np()
3714 // first to kill every thread on the thread list. Because this list is
3715 // not reset by fork() (see notes above), execve() will instead kill
3716 // every thread in the parent process. We know this is the only thread
3717 // in the new process, so make a system call directly.
3718 // IA64 should use normal execve() from glibc to match the glibc fork()
3719 // above.
3720 execve("/bin/sh", (char* const*)argv, environ);
3721
3722 // execve failed
3723 _exit(-1);
3724
3725 } else {
3726 // copied from J2SE ..._waitForProcessExit() in UNIXProcess_md.c; we don't
3727 // care about the actual exit code, for now.
3728
3729 int status;
3730
3731 // Wait for the child process to exit. This returns immediately if
3732 // the child has already exited. */
3733 while (waitpid(pid, &status, 0) < 0) {
3734 switch (errno) {
3735 case ECHILD: return 0;
3736 case EINTR: break;
3737 default: return -1;
3738 }
3739 }
3740
3741 if (WIFEXITED(status)) {
3742 // The child exited normally; get its exit code.
3743 return WEXITSTATUS(status);
3744 } else if (WIFSIGNALED(status)) {
3745 // The child exited because of a signal
3746 // The best value to return is 0x80 + signal number,
3747 // because that is what all Unix shells do, and because
3748 // it allows callers to distinguish between process exit and
3749 // process death by signal.
3750 return 0x80 + WTERMSIG(status);
3751 } else {
3752 // Unknown exit code; pass it through
3753 return status;
3754 }
3755 }
3756 }
3757
3758 // Get the kern.corefile setting, or otherwise the default path to the core file
3759 // Returns the length of the string
3760 int os::get_core_path(char* buffer, size_t bufferSize) {
3761 int n = 0;
3762 #ifdef __APPLE__
3763 char coreinfo[MAX_PATH];
3764 size_t sz = sizeof(coreinfo);
3765 int ret = sysctlbyname("kern.corefile", coreinfo, &sz, NULL, 0);
3766 if (ret == 0) {
3767 char *pid_pos = strstr(coreinfo, "%P");
3768 // skip over the "%P" to preserve any optional custom user pattern
3769 const char* tail = (pid_pos != NULL) ? (pid_pos + 2) : "";
3770
3771 if (pid_pos != NULL) {
3772 *pid_pos = '\0';
3773 n = jio_snprintf(buffer, bufferSize, "%s%d%s", coreinfo, os::current_process_id(), tail);
3774 } else {
3775 n = jio_snprintf(buffer, bufferSize, "%s", coreinfo);
3776 }
3777 } else
3778 #endif
3779 {
3780 n = jio_snprintf(buffer, bufferSize, "/cores/core.%d", os::current_process_id());
3781 }
3782 // Truncate if theoretical string was longer than bufferSize
3783 n = MIN2(n, (int)bufferSize);
3784
3785 return n;
3786 }
3787
3788 bool os::supports_map_sync() {
3789 return false;
3790 }
3791
3792 #ifndef PRODUCT
3793 void TestReserveMemorySpecial_test() {
3794 // No tests available for this platform
3795 }
3796 #endif
3797
3798 bool os::start_debugging(char *buf, int buflen) {
3799 int len = (int)strlen(buf);
3800 char *p = &buf[len];
3801
3802 jio_snprintf(p, buflen-len,
3803 "\n\n"
3804 "Do you want to debug the problem?\n\n"
3805 "To debug, run 'gdb /proc/%d/exe %d'; then switch to thread " INTX_FORMAT " (" INTPTR_FORMAT ")\n"
3806 "Enter 'yes' to launch gdb automatically (PATH must include gdb)\n"
3807 "Otherwise, press RETURN to abort...",
3808 os::current_process_id(), os::current_process_id(),
3809 os::current_thread_id(), os::current_thread_id());
3810
3811 bool yes = os::message_box("Unexpected Error", buf);
3812
3813 if (yes) {
3814 // yes, user asked VM to launch debugger
3815 jio_snprintf(buf, sizeof(buf), "gdb /proc/%d/exe %d",
3816 os::current_process_id(), os::current_process_id());
3817
3818 os::fork_and_exec(buf);
3819 yes = false;
3820 }
3821 return yes;
3822 }